McGr a w- Hi l l Co m p a n y, In c. Ja m e s H . McGr a w, President
E . J . Me h r e n, Vice-President
D e v o te d to t h e O p e r a tin g , T e c h n ic a l a n d B u s in e s s
P r o b le m s o f t h e C o a l- M i n i n ^ 'i n d u s t r y Engineering E ditorR . Da w s o n Ha l l
Volume 28 N EW YORK, SEPTEM B ER 3, 1925 N um ber 10
T h e P u b lic and th e A n th racite S trik e
T
H E S IL E N C E O F S U S P E N S IO N h a s s e ttle d down upon th e a n th r a c ite m in in g d is tric ts o f n o r th e a s te rn P e n n sy lv a n ia . T h e f r a n tic peace effo rts of th e b u sin ess m en of th e reg io n , w ho m u s t becom e th e u n w illin g fin an ciers o f th e co n test, have gone th e w ay o f th e co n ciliato ry w o rd s of th e p ro d u c e rs p u t f o r th a f t e r P r e s id e n t Jo h n L. L ew is of th e U n ite d M ine W o rk ers h ad re tu rn e d to A tla n tic C ity in a th u n d e r o f u ltim a tu m s. B a r r in g in te rv e n tio n , v ic to ry is p ro m ise d to th e sid e w ith th e lo n g e st p u rs e an d th e g r e a te s t e n d u ra n c e — and th e odds, u n d e r such co nditions, a re n o t chalked up a g a in s t th e m in e rs a t th e fig u re th e pu b lic com m only th in k s.
A s h re w d e r p sy ch o lo g ist th a n h is opponents, M r.
L ew is w as q u ick to seize th e o p p o rtu n ity to use th e e ffo rts of th e co m m ittee w h ich he h a d in su lte d in h is firs t com m ents on th e a c tiv itie s o f th e b u sin ess m en as a m ed iu m f o r th e p ro m u lg a tio n o f som e effective p ro p a g a n d a d e sig n ed to re h a b ilita te th e u n io n cause in th e p u b lic eye. T h e o p e ra to rs, d isp la y in g m o re in te l
lectu al h o n e sty th a n finesse, p assed by th e o p p o rtu n ity to re p ly to M r. L ew is in k in d . T he u n io n le a d e r w as le f t d ic ta tin g te rm s o f re su m p tio n w hich th e o p e ra to rs could accept only w ith t h e ir to n g u es in th e ir cheeks an d th e y could n o t b rin g them selves to reopen n eg o tia tio n s
on a b a sis of h y p o crisy .
A lth o u g h th e public now m oans th a t th e m in e rs an d th e o p e ra to rs hav e com pletely d isre g a rd e d its in te re s ts in th e c o n tro v e rsy , th e f a c t is th a t th e public, by its e a rlie r in a c tio n , h a s definitely s ta te d its p o sitio n . T he o p e ra to rs e n te re d th e w ag e conferen ces w ith tw o a n n o unced o b jectiv e s— a r b itr a tio n of all q u estio n s upon w hich th e co n ferees could re ach no a g re e m e n t so t h a t a su sp en sio n m ig h t be avoided an d o pposition to a n y ch an g es w hich w ould in c re a se th e cost of coal to th e consum er. To n e ith e r proposal w ould th e m in e rs give t h e i r a sse n t. To th e firs t pro p o sal th e y voiced a m o st v ig o ro u s, n o t to say b itte r , d issen t. A f te r tr o t t i n g o u t a few old frie n d s , such as f r e ig h t ra te s , p ro fits a n d th e h a z a rd s o f th e in d u s try , th e m in e rs m ade it p la in t h a t th e y would n o t a g re e to th e sto p p in g of th e ste a d y ad vance of w ages.
T he public w as fra n k ly en am o u red w ith th e proposal to check in c reases in fu el p ric e s. I t seem ed, f o r th e m o st p a r t, s tra n g e ly in d iffe re n t to th e su g g e stio n to avoid a susp en sio n . I t s a ttitu d e , reflected in th e n o n ch alance in evidence a t W a sh in g to n an d S w am pscott, w as one of “le t ’em fig h t i t o u t; we should w o rry .”
W hen th e public ' an d th e a d m in is tra tio n m ig h t have th ro w n th e w e ig h t of t h e ir influence on th e sid e o f a r b itr a tio n a s pu b lic p ro te c tio n a g a in s t a n in te r r u p tio n to th e p ro d u c tio n o f h a r d coal, b o th w ere silen t.
S ince th e public, in th e w eeks d u rin g w h ich th e o p er
a to r s a n d m in e rs w e re m e e tin g a t A tla n tic C ity elected to a d o p t a “h a n d s off” policy, th e in d u s tr y to d a y h a s th e r ig h t to d em and t h a t th e pu b lic a n d th e a d m in is
tr a tio n a t W a sh in g to n co n tin u e t h a t policy of n o n
in terferen ce . T he p re s s u re th a t in tim es p a s t h a s com
pelled th e o p e ra to rs to a g re e to s e ttle m e n ts fra m e d in a s p ir it o f f e a r should n o t be ex erted . F rie n d ly offices, o f course, a re alw ays in o rd er, b u t th e pu b lic h as su rre n d e re d w h a te v e r r ig h t i t m ay hav e h ad to d ictate te rm s. A sense of f a i r play should keep W ash in g to n as calm w hen excited N ew E n g la n d C o n g ress
m en descend upon i t w ith th e c ry o f “peace a t an y p rice” as i t is today. T he pu b lic acted as if i t knew w h a t it w a n te d : le t i t n o t la te r com plain of th e b a rg a in .
D o n ’t H am strin g th e B u reau o f M ines
T
H E LONG D E L A Y in choosing a d ire c to r f o r th e B u reau of M ines h a s c re a te d a s itu a tio n in W ash in g to n th a t m e rits som e a tte n tio n fro m th e coal in d u stry . T he proposal h a s been p u t f o r th th a t th is b u re a u and th e B u re a u o f S ta n d a rd s be d ire c te d by th e sam e executive. O pposition to th is should r is e a t once fro m m en and o rg a n iz a tio n s in te re s te d in coal. T he B u re a u of S ta n d a rd s is a la b o ra to ry en g ag ed la rg e ly in e x p e ri
m ents of a physical or chem ical c h a ra c te r. Som e o f th ese ex p erim en ts have a d ire c t a p p licatio n to m in in g b u t th ese a re by no m ean s th e c o n tro llin g a c tiv itie s o f th e B ureau.
T he B u re a u o f M ines is p e rfo rm in g an d m u st con
tin u e to p e rfo rm a valuable serv ice to th e coal in d u s try as well as to o th e r in d u s tria l g ro u p s w hose b u sin ess in te re s ts a re bound up w ith th e n a tio n ’s m in e ra l resources, and i t c e rta in ly should n o t be m ade su b se rv ie n t to o r d o m in ated by an y o th e r g o v e rn m e n t bu reau . The in d u s try should m ake i t clear to everybody in W ash in g to n th a t i t h a s little p atien ce w ith b u re a u riv a lry or p erso n al am b itio n s.
A n o p p o rtu n ity now e x ists to c e n tra liz e th e m in in g activ itie s of th e fe d e ra l g o v e rn m e n t w h ere th e r e is a good chance to have i t m ade a g ra n d div isio n o f a d e p artm e n t w ith re co g n itio n o f m in in g in th e d e p a rt
m e n t’s title . N ow t h a t i t is s e ttle d th a t th e B u re a u of M ines is to be u n d e r th e ju r is d ic tio n o f a frie n d ly se cretary , it is fe lt th a t th e in d u s tr y h a s e v e ry th in g to g ain and n o th in g to lose by s tre n g th e n in g an d building up its service.
T im e to M ake R ep airs
N
OW T H A T T H E a n th r a c ite in d u s tr y is s h u t down, m any o p p o rtu n itie s a re p re se n te d f o r im p ro v em ents. W hen th in g s a r e g o in g s tro n g little tim e is available f o r p la n n in g ch an g es w h ich w ill re s u lt in b e tte r o p eratio n , b u t d u rin g a su sp en sio n th e officials and e n g in eers w ill h av e a chance to look a ro u n d an d survey th e p ro p e rtie s w ith th is id ea in m ind.
Some will say th a t th e se m en w ill be su p e rv isin g th e care of pum ps, h o ists, etc. o r k eep in g th e im p o rta n t equipm ent in r e p a ir a n d th u s w ill find little tim e to do co n stru ctiv e w ork. H ow ever, is n ’t th is a n occasion to plan f o r th e f u tu r e ? T h ese m en w ill now be o u t in th é field w h ere th e y w ill be able to o b ta in f o r them selves
305
306 C O A L A G E Vol. 28, N o. 10
first-h a n d in fo rm a tio n of th e co n d itio n s s u rro u n d in g th e places a n d sy stem s th a t should be im proved.
B u t asid e fro m th e se m en th e re a re alw ays m a n y o th e rs w ho can be em ployed re p a irin g a p p a ra tu s w hich, d u rin g th e g r e a t pu sh b efo re th e su spension, w as ta x e d up to o r even beyond its lim it. E v en in th e o rd in a ry wox-k o f ta k in g ca re o f eq u ip m en t d u rin g th e su spension, occasions w ill be fo u n d to do th e w o rk b e tte r an d th u s p u t th e eq u ip m en t in good condition f o r re su m p tio n o f a c tiv itie s. F o r exam ple, a s to ra g e b a tte r y on a loco
m otive ra re ly receives p ro p e r a tte n tio n d u rin g o p e ra t
in g periods, b u t now i t can be re p le n ish ed w ith acid a n d c h arg ed so as to b rin g i t back to good co n d itio n . T hen again, co n sid er th e m ine locom otives: n e a rly every one o f th em h a s so m eth in g t h a t should be re p a ire d ; h e a d lig h ts, b ra k e shoes an d b e a rin g s could all be r e p a ire d o r a t le a st a d ju ste d .
W ith th e re su m p tio n o f w ork, re g a rd le ss of th e r e su lts of th e p re s e n t w age co n tro v ersy , th e m in es m u st in f u tu r e be o p e ra te d so a s to keep th e sellin g p ric e of coal a s low a s possible. T h e re fo re, th e d ay h a s a rriv e d to ta k e tim e by th e forelock.
M ake H aste S low ly
O
F A L L R E V E A L IN G th in g s few a re m o re in te r e s tin g th a n th e slow “m ovie” th a t show s us m otions slowed down to m eet th e im p e rfe c tio n s o f th e h u m a n eye. T hose m otions could n o t in m o st cases be duplicated a t such speed. G ra v ity an d m u sc u la r effo rt w o rk m ore ra p id ly , so th a t th e scree n p ic tu re is a n im possible one.T h is fu rn is h e s a n illu s tra tio n in th e a r t o f m o d ern m in in g . A few com panies a re tr y in g to te s t ro o f actio n w ith c e rta in specific co n d itio n s of o p e ra tio n a n d a re u sin g th e o rd in a ry slow m eth o d s o f lo ad in g coal in o rd e r th a t th e y m ay discover w h a t w ill be th e ro o f actio n w ith th o se sam e co n d itio n s a n d w ith m o re ra p id loading m ethods. B u t w ith such e x p erim e n ts th e y can g e t only m islead in g re su lts. T he slow “ m ovie” re p r e se n ts n o th in g tru ly . S o m eth in g esse n tia lly d iffe re n t w ould h appen i f w e tr ie d to im ita te th o se m o tio n s a t such slow speed. S im ila rly th e ro o f u n d e rm in e d slowly will n o t a c t a s i t would if speedily u n d erm in e d .
N o th in g is m ore c e rta in th a n t h a t ro o f ac tio n is com plicated in th e extrem e. I t is a p ro g re ssiv e s e rie s of m ovem ents, a n d th e y ta k e place in a s e ria l o rd e r.
One actio n m u st w a it f o r a n o th e r an d all o f th e m ta k e a c e rta in le n g th of tim e. T h is is no th e o ry . E x p ei'i- ence h as show n t h a t speed in o p e ra tio n m odifies ro o f ac tio n p ro fo u n d ly and w h a t w ould be a f a ilu r e w ith slow e x tra c tio n is a com plete success w h en coal is rem oved w ith speed.
P e r so n n el B u ild in g
O
P P O R T U N IT IE S f o r im p ro v in g th e p erso n n el a t th e m ines a re offei'ed by th e se lean tim e s in in d u stry , and th e y should be used w h en ev er possible.M en who a re h a b itu a l ris k ta k e rs, should be le t o u t of th e o rg a n iz a tio n . T h e bootlegger, th e m an who is a bad citizen o r who h a s a reco rd fo r w o rk in g s h o rt tim e should be d ropped w hen any m en a re le t out.
A n in d u s try is no b e tte r th a n its personnel. A b u s i
n e ss t h a t h a s th e re co rd o f h a v in g ro u g h c h a ra c te rs w o rk in g in i t does n o t s ta n d well w ith th e public. I f th e coal in d u s try h a d a b e tte r class of m in ers, th e o p e ra to r s w ould be in b e tte r fa v o r an d h av e fe w e r s trik e s . Som e m en m a y a rg u e t h a t th e y w ill g e t m o re coal fro m
ro u g h n eck s th a n fro m m en w ith less of fire in th e ir blood, b u t th o se w ho a c t on th a t p rin c ip le w ill find b e fo re long t h a t all th e ir m en w ill be of t h a t class.
Selective em ploym ent is th e b a sis of success. A b ig burly, ro u g h m an m ay be a good to n n a g e p ro d u cer, b u t h e m ay, n ev erth eless, d e stro y th e m o rale o f th e p e r
sonnel and so be o f m ore h a rm th a n good. W hen a m an finds t h a t s ta n d in g to o rd e r is necessai-y to r e ta in h is jo b in a m in in g v illag e h e w ill s tr a ig h te n up an d th e tow n w ill be m ade en d u ra b le to th e peaceable citizen an d h is w ife. I f th e ro u g h n e c k finds th e atm o sp h e re re s tr a in in g an d d isp le a sin g le t h im ta k e th e open road.
T he coal in d u s tr y is ju d g e d by th e m en i t h ire s, a n d by th e ir w ives an d fam ilie s.
S o ft C oal’s Job
T
H E R E IS A C E R T A IN p le a su re in tu r n in g fro m a n th r a c ite ’s tro u b le s to a c o n tem p latio n o f s o ft coal’s serv ice to th e co u n try . T h e h a r v e s t is on. T h e n a tio n is filling its elev ato rs, its w areh o u ses, its s to r ag e y a rd s. I t is a d v a n c in g in to th e a u tu m n w ith a confidence b o rn o f econom ic v irility . One excellent in d icatio n o f th is co n d itio n is fo u n d in th e m o st re c e n t C ar S ervice D iv isio n re p o r t fro m th e A m e ric a n R a ilw ay A sso ciatio n .
F o r th e fifth consecutive w eek, lo ad in g o f re v en u e f r e ig h t exceeded one m illion c a rs a w eek, th e to ta l f o r th e w eek ended A u g . 15 h a v in g been 1,064,793 c a rs.
T h is could m ean n o th in g less th a n b u sin ess h e a lth f o r th e c o u n try . T h e n u m b e r o f c a rs loaded w ith rev en u e f r e ig h t up to d a te th is y e a r h a s exceeded all p rev io u s y e a rs an d th e w eek of A ug. 15 w as th e g r e a te s t w eek of 1925. I t w as 111,385 c a rs in excess o f th e c o rre spo n d in g w eek la s t y e a r an d 24,855 c a rs a h e a d o f 1923.
T he m ovem ent o f coal to m a rk e t is, o f course, im p o r
t a n t in th e se figures. Coal lo ad in g f o r th e w eek to ta le d 190,979 c a rs w h ich w as 45,716 c a rs g r e a te r th a n th e sam e w eek a y e a r ago an d 1,800 c a rs o v er 1923.
H ow ever, i t is n o t coal alone t h a t sw ells th e f r e ig h t m ovem ent to its u n w o n ted flood. L ivestock lo ad in g s w ere 2,153 c a rs ah ead o f la s t y e a r. L ess th a n carlo ad f r e ig h t to ta le d 259,210 c a rs w h ich exceeded la s t y e a r by 17,272 c a rs a n d tw o y e a rs ago b y 17,§22 c a rs. H e re is a s u re in d ic a tio n o f b u sin e ss s tr e n g th . M iscellane
ous f r e ig h t w as 33,934 c a rs a h e a d o f 1924 a n d 30,308 c a rs in excess of 1923. A n d so i t goes.
All th is heav y flow o f th e n a tio n ’s f r e ig h t is m oved by s o ft coal sold to th e ra ilro a d s a t a n a v e ra g e p ric e low enough to s a tis f y an y o n e b a r r in g possib ly th e h a rd - boiled ra ilro a d coal b u y e r w hose p ro fe ssio n i t is to be absolutely in s a tia b le . T h e tre m e n d o u s volum e o f m a n u fa c tu re s re p re se n te d by th e f r e i g h t flood w as p ro duced w ith th e a id o f coal w h ich h a s bean low er in p ric e th is su m m er in p ro p o rtio n to th e co st o f p ro d u c tio n th a n ev er b efo re— th is w eek th e Coal A g e n a tio n a l a v e ra g e is b u t §2.10 even a f t e r th e a u tu m n ris e h a d s e t in. Coal’s serv ice deeply effects th e w hole econom ic fa b ric of t h e ' la n d and, f o r once, coal ca n n o t be p e tu la n tly blam ed f o r chaos in in d u s tr y g en erally , f o r th e re is no chaos.
S o ft coal is a b u n d a n tly av ailab le a t low co st a s th e c o u n try b e g in s a n o th e r w in te r a n d th e ra ilro a d s a re a d m ira b ly equipped to d eliv er it. W e can only hope t h a t Jo h n L ew is’ b lin d lu s t f o r co m b at w ill n o t im pel h im to r is k callin g h is m en o u t o f b itu m in o u s m in es th is fall f o r p u n itiv e p u rp o se s o r f o r a n y o th e r reaso n . S o ft coal o u g h t n o t to be d e p riv ed b y th e m in e rs o f its fu ll o p p o rtu n ity to c o n tin u e se rv in g A m erica.
In the Coal Wilds of U tah
L o o k in g - d o w n t h e i n c l i n e f r o m t h e S t a n d a r d v l l l e m i n e in b o t t o m f o r e g r o u n d t o t h e t o w n a n d t i p p l e i n t h e m i d d l e g r o u n d a t t h e f o o t o f t h e s n o w y m o u n t a i n .
S e p t e m b e r 3; 1 9 2 S' C O A L A G E
Utah Storms Burst Futilely About Meeting o f Rocky M ountain Coal Mining Institute
U p set P ro g ra m a t .price—E n g in eers arid sTLoading M ach in es/ Conveyors, R ock/Ö ust
fW ash o u ts Do N ot
E xecutives Discuss'JLoacung iviacmnes, co nveyors, Kock JDusit and O th e r T ech n ical Subjects Im p o rta n t to th e In d u stry
\ JB y R . D aw son H all ft G
E n g i n e e r i n g E d i t o r o f G o a l A g e
T
Y P IC A L U ta h A u g u s t sto rm s w ith h a ll-h o u r floods r u in in g ro a d s a p d ^ d is ru p tin g ra ilro a d s e rv ice did n o t sto p th e su m m e r m e e jin g 'o f th e R ocky M o u n ta in Coal M in in g I n s titu te a t ^ r i c e , U ta h , A ug.26, 27 an d 28. » ^ E n g in e e rs, executives, a n d o th e r coal m in in g m en in c lu d in g a good m a n y re p re s e n ta tiv e s o f m a c h in e ry an d eq u ip m e n t com panies assem bled in la rg e n u m b e r a n d m ade th e to w n a b u sy place w ith th e ir d iscussions, t h e ir d in n e rs a n d t h e i r g ro u p g o in g s and com ings to n e a rb y m in e s w hich hav e m ad e C arb o n C ounty n o te w o rth y in coal p ro d u ctio n . R ock d u stin g , m ach in e lo a d in g a n d th e u s e of u n d e rg ro u n d conveyors w ere th e m a in su b je c ts co n sid ered , b u t th e se by no m ean s filled th e p ro g ra m .
D esp ite th e absence o f J . B. M ark s, th e p re sid e n t, who te le g ra p h e d t h a t he could n o t be p re s e n t b ecause of e x tre m e p r e s s u re o f b u sin e ss, th e I n s titu te m e a su re d th is y e a r fu lly up to its fo rm e r reco rd s, a la rg e crow d h a v in g g a th e re d in th e S ta r T h e a te r w hen th e m e e tin g w as opened b y B en ed ict S h u b a r t th e se c re ta ry . G eorge B. P ry d e p re sid e d . T h e slides f o r th e p a p e r on “ E lec
t r i c S h o tfirin g ” n o t h a v in g been m ad e a n d th e p a p e r its e lf h a v in g been delayed in th e m ails, th e a rtic le b y R o b e rt W illiam s, J r . could n o t be p re se n te d . A film m ade b y th e E . I. d u P o n t de N em o u rs Co., e n title d “T he S to ry o f D y n a m ite ” w as show n by A. E . A n d erso n .
J . M. J e n n in g s d esc rib ed th e N ew H iaw ath a , tip p le o f th e U n ite d S ta te s F u e l Co. w h ich th e I n s titu te p lan n ed to v is it in th e a fte rn o o n . D u rin g th e n ig h t th e ro a d betw een P ric e a n d H ia w a th a h a d been w ash ed o u t, b u t a s th e w e a th e r w as p ro p itio u s in th e m o rn in g th e ro ad co m m issio n ers m a n a g e d to p ro v id e a n easy d e to u r dow n in to a n d up o u t o f th e a rro y o w h e re th e w a sh o u t o ccu rred . T h e t r i p to H ia w a th a over th e d e s e rt w as p le a sa n tly accom plished b u t th e sm ilin g little v illag e w as b a re ly rea c h e d w hen a h ea v y sto rm b roke. H ow ever, th e • g u e s ts w ere affo rd ed a fine sp re a d in th e am u se m en t hall, a n d a f t e r i t w as ov er th e y v is ite d th e tip p le w h ich is one o f th e fin est in th e W est.
In th e ev en in g th e v is ito r s p a ra d e d th e s tr e e t fro m th e Savoy H o tel to th e T a b e rn a cle o f th e L a tte r D ay S a in ts w h e re a n in fo rm a l b a n q u e t in th e b a se m e n t o f th e b u ild in g w as a d d re sse d b y th e m a y o r o f P ric e and sev eral le a d in g m in in g m en, th e e n tra n c e to th e b a n q u e t hall b e in g d eco rate d to look lik e a m in e a n d th e p a ssa g e w ays b e in g labeled lik e its u n d e rg ro u n d w o rk in g s. On th e w a y one of th e d istin g u ish e d g u e s ts w a s seized an d tre a te d to first-a id , th e am b u lan ce b ein g re q u isitio n e d to c a r r y h im to h is d e stin a tio n . T h e ev en in g closed w ith a ball in th e C ity H all.
A t th e m o rn in g m e e tin g o f T h u rs d a y A. W . D ick in son p re se n te d a n in te r e s tin g rev iew of th e m a n y fo rm s of lo ad in g m ach in es, in c lu d in g th e H a m ilto n m achine, th e Je ffre y e n tr y m ach in e, th e O’Toole an d M cK inley c u ttin g and lo ad in g m achines, th e T h ew “ S” lo ad er, th e
Jo y loaders 4, 5 a n d 6 B.U., th e Coloder, th e M yers W h a ley, th e Riley, th e Stockley, th e B u rn ell, th e G oodm an H y d ra u lic loader, th e G oodm an ty p e s A a n d B s c ra p e rs , th e Ace, th e M acE achen a n d th e J e ffre y P itc a r lo a d ers.
H e also gave m uch in fo rm a tio n r e g a r d in g th e M ovor, F a irm o n t, Echoff, L in k -B elt, an d J e ffre y sectio n al con
veyors and th e Je ffre y 44-A conveyor loader.' C le a r
ances, le n g th s and pow er re q u ire d w ere g iv en fo r each loading m achine.
M r. D ickinson th e n re a d G len A. K n o x ’s p a p e r on th e o p e ratio n s a t th e S w e e tw a te r m in e o f th e G unn- Q uealy Coal Co., w h e re conveyors hav e been used w ith g r e a t success. M odifications o f longw all a re b e in g used.
A t first th e faces w e re m ad e a t a n an g le a b o u t h a lf w ay betw een th e s tr ik e a n d p itc h , th e conveyors proceeding down th e p itc h as th e c u ttin g p ro g re sse d . L a te r th e faces w ere m ad e a t a s im ila r angle, b u t th e
308 C O A L A G E Vo l. 28, No. 10
m a in conveyors w ere m oved along th e s tr ik e . F in a lly th e fa ce s w ere alig n e d w ith th e p itc h , th e m a in con
veyors b ein g laid in th e d ire c tio n o f th e s trik e . A t th e conclusion o f M r. K nox’s p a p e r O. G. S h a r r e r re a d an in te re s tin g account o f h is ex p erien ces w ith m echanical lo ad ers in c e n tra l P en n sy lv a n ia , d e sc rib in g h is e a rly o p e ra tio n o f Jo y lo ad ers w h ile w ith th e P e n n sy lv a n ia Coal Co., d e c la rin g t h a t th e r e w e re no p a rtic u la r a d v a n ta g e s in a com plicated tr a c k sy stem as th e expense of la y in g an d re p a ir in g e a ts up th e p ro fits th a t m ig h t accrue due to g r e a te r speed in h a n d lin g cars. H e also described ex p e rim e n ts w ith sc ra p e rs w h ere th e coal w as only 30 in . th ic k . D ifficulties aro se because th e m eth o d of o p e ra tio n could n o t be m odified to s u it th e sc ra p e r, because th e m in es w o rk ed ir r e g u larly and because a scale could n o t be o b tain ed f o r th is ty p e of w ork. O th e r te s ts of th e M yers-W haley and Je ffre y h e a d in g m ach in es w ere described. T h e V -system of W est V irg in ia did n o t seem s u ita b le fo r P e n n sy lv an ia conditions, a cco rd in g to M r. S h a r r e r .
M r. S h a r r e r said th a t too m an y m en should n o t be p u t on th e jo b a t first, because i f th e n u m b e r is red u ced la te r m isu n d e rsta n d in g s a rise . H e declared t h a t i t w as difficult to use enough w a te r to p re v e n t th e c re a tio n of excessive d ust. In h is opinion th e h a u la g e problem w as n o t th e p rin c ip a l difficulty a n d t h a t lo ad ers w e re so e r r a tic in p e rfo rm a n c e t h a t i t w ould n o t p a y to give m axim um h a u la g e fa c ilitie s till i t w as m ade c lear t h a t th e load in g eq u ip m en t w ould w o rk w ith o u t delays o th e r th a n th o se a ris in g fro m h a u lag e. W ith all M r. S h a r- r e r ’s c ritic ism h e w as confident t h a t th e f u tu r e of th e m achine lo ad e r w as a ssu re d , an d t h a t success w ould be achieved “in th e n e x t fe w y e a rs .”
In th e h a ste to reach th e lunch p ro v id ed by th e S p rin g Canyon Coal Co., th e a d d re ss b y G. A. M u rphy, g e n era l m a n a g e r of th e com pany w as o m itted .
Discuss Me c h a n i c a l Lo a d in g
In th e evening a session w as held in th e C arbon C ounty H ig h School a t w h ich th e a rtic le s on m ech an ical load in g w e re -e x h au stiv ely discussed. B en ed ict S h u b a rt fa v o red th e use o f m eta l conveyors a n d sa id t h a t belt conveyors, th o u g h m uch used in E n g la n d , w e re alm o st unknow n f o r fa ce o p e ra tio n s in th e U n ite d S ta te s. H e re g a rd e d th e H . C. F ric k Coke Co. b e lt a t Colonial M ines as so m e th in g m ore th a n m e re m a in h a u la g e . I t corresponded m ore n e a rly to ra ilro a d tr a n s p o r ta tio n and th e co n tin u ed o p eratio n o f th e b e lt w ith o u t in ju r y w as la rg ely due to th e fa c t t h a t th e coal w as n o t b ein g deposited on th e belt a t all s o rts o f an g le s b u t w as being c a rrie d fo rw a rd w ith o u t d istu rb a n c e on its flat su rface s.
Jo h n F o r r e s te r said th a t, in h is belief, th e re aso n w hy m etal conveyors w ere p r e fe rre d w as b ecause th e y could be len g th en ed an d sh o rte n e d a t p le a su re an d so th e y could be o p erated w ith g r e a te r flex ib ility th a n b elt conveyors. W. C. H olm an sa id t h a t to ob v iate b ru s h in g w h ere th e coal w as low th e P h elp s D odge Co. w as u sin g tw o Je ffre y b elt conveyors in tandem .
T he tim e-honored q uestion a s to w h e th e r th e in tro duction of longw all and conveyors h ad re su lte d in a la rg e r p e rc e n ta g e of th e sm aller sizes of coal w as in tr o duced and J . M. Je n n in g s sa id th a t M r. K nox w as g e t
tin g u n u su ally la rg e coal w ith conveyors, as lo n g as h e so u g h t to g e t th e la r g e r sizes. L a te r th e m a rk e t re q u ire d sm aller coal an d accordingly he h a d i t b ro k en up sm aller w ith h e a v ie r shooting.
• O tto H e rre ś sa id t h a t w ith longw all w o rk in g such
as th a t in o p e ra tio n a t S w e e tw a te r th e coal w ould be b roken up in to sm a lle r sizes due to th e c ru sh . G eorge B. P ry d e took a d iffe re n t view . L ongw all w a s n o t as d e s tru c tiv e to th e in te g r ity of coal a s sh o o tin g fro m th e solid a n d t h a t w as th e p ra c tic e a t S w e e tw a te r.
H e would say t h a t th e p re s e n t m eth o d s h a d n o t in creased th e p e rc e n ta g e o f slack.
T he discu ssio n th e n s h ifte d to h a z a rd s. M r. D ick
inson sa id th e re w as a n in c re a se o f d u s t in m a ch in e loading, especially w ith th e M cK inley lo ad in g a n d c u t
tin g m ach in e w h ich w as ex trem ely d u sty . M r. F o r r e s te r d e c la re d . th a t m o re d u s t w as to be expected because, w hen lo ad in g by m achine, th e coal is sh o t h a r d e r in o rd e r to m ake i t e a s ie r f o r th e m a ch in e to p ick i t u p . ' H ow ever, he believed th e r e w as less h a z a rd because, w ith th e closer su p e rv isio n possible by re a so n o f th e c o n c e n tra tio n of o p e ra tio n s, i t w as easy to k eep dciwn th e d ust.
Co n c e n t r a t io n Ha s Da n g e r s
E u g e n e M cA uliffe believed t h a t m a ch in e lo ad in g w as m ore d u sty th a n h a n d lo ading. D. H a r r in g to n th o u g h t th e h a z a rd s g r e a t l y in c re a se d by m o d ern m eth o d s of lo ad in g .- N o t only did th e m eth o d s in c re a se th e q u a n tity o f d u s t b u t th e y also, in c re a se d th e ra p id ity of m in in g a n d th e in c re a se d q u a n tity o f coal b ro k en down caused la rg e q u a n titie s o f g as to be released. T h e n u m b e r of m o to rs on lo ad in g m ac h in es a n d conveyors g re a tly added to th e h a z a rd . No m o re d a n g e ro u s places could be fo u n d f o r such m o to rs th a n a t th e w o rk in g face w h e re th e re w ere excessive q u a n titie s of p u re coal d u st and w h ere th e r e w as m ore g a s th a n a t an y o th e r p oint. In .rep ly to M r. H e r r e s ’ su g g e stio n th a t m ach in e load in g w as s a fe r becau se o f th e c o n c e n tra tio n an d th e p o ssib ility of close su p e rv isio n th a t w e n t w ith such co n c e n tra tio n , M r. H a r r in g to n sa id t h a t h e believed co n c e n tra tio n likely to p ro v e a so u rce o f d a n g e r r a th e r th a n its p re v e n tiv e . A t D olom ite, Ala., a n u m b e r of m en h ad assem bled an d as a re s u lt w h a t w as a re la tiv e ly sm all explosion killed a la rg e n u m b e r of m en. C oncen
tr a tio n , he said, is n o t w ith o u t its d a n g e rs in m in e o p eratio n .
T o M r. M cA uliffe th e se a rg u m e n ts did n o t appeal.
F ew places, he av e rre d , w e re b e tte r sp rin k led th a n th e w o rk in g places in a m a ch in e-lo ad in g m ine. T h e re w as m ore su p erv isio n th e re , and th e re could be m o re v en
tila tio n . In th is b e lie f th e m ach in e lo ad in g w ould in crease s a fe ty by t h a t v e ry co n c e n tra tio n t h a t M r.
H a rrin g to n deplored.
A t th e close of th is d iscu ssio n on th e s a fe ty of m e
chan ical lo ad in g D. H a r r in g to n re a d a n a rtic le on rock d u s tin g p ra c tic e in th e R ocky M o u n tain re g io n and L. C. C lare one on “M u d ite ’s R elatio n to N a tu r e .” M r.
H a rrin g to n sa id th a t ow ing to a lack o f fu n d s th e U. S.
B u re a u o f M ines h ad m ade no e x p e rim e n ts in th e B ru ceto n m ine in th e use of m udite.
H. A. W ylan, of S u p e rio r, W yo., sa id th a t th e w e ttin g down of em p ty c a rs w as m ore im p o rta n t th a n th e sp rin k lin g o f loads. C a rs should be sp rin k le d w hen e n te rin g th e m in e as well as w hen leav in g them . T he
“e m p ty ” c a r d is trib u te d m ore d u s t and finer d u st th a n th e loaded car.
E . K. J u d d sa id th a t th o u g h ’g y p su m h ad been found disposed to fall off th e rib s w hen b e in g applied, he believed th a t its m e rits as an in e r t m a te ria l should not be overlooked because it ab so rb ed h e a t ra p id ly a n d th a t seem ed a p rim a ry q u a lity in a good ex p lo sio n -p rev en tiv e dust. T he B u re a u o f M ines h ad m ade endeavors to
Se p t e m b e r 3, 1925 C O A L A G E 309
H iaw atha H as a Fine Tipple
T h e i n s t i t u t e j o u r n e y e d f r o m P r i c e t o H i a w a t h a in s p i t e o f s t o r m s a n d w a s h e d - o u t r o a d s . T h i s p l a n t , o f t h e U n i t e d S t a t e s F u e l C o ., o n e o f U t a h ’s b e s t , w a s v i s i t e d . I t r e c e i v e s c o a l f r o m a n i n c l i n e o n w h i c h 1 6 - c a r t r i p s o p e r a t e . I t c a n s iz e , c l e a n a n d l o a d 40 0 t o n s a n h o u r . N e a r l y 20 s i z e s a r e w i t h i n t h e r a n g e o f t h e h o r i z o n t a l s c r e e n s .
a s c e rta in th e te m p e ra tu re s re ach ed m o m e n ta rily in m in e explosions. Gold a n d silv er fo il w ere susp en d ed in th e B ru c eto n e x p e rim e n ta l m ine. T h e firs t w as m elted only once a n d th e second fre q u e n tly w as fo u n d to be fu sed , sh o w in g th a t th e te m p e ra tu re w as som e
tim e s above 1,832 deg. F.
T he specific h e a ts of e a rth y bodies used f o r rock d u s t
in g ra n g e g e n e ra lly fro m 0.19 to 0.22. T a k in g th e la rg e r fig u re a n d a ssu m in g th e te m p e ra tu re to ris e 1,765 deg. th e n u m b e r of B r itis h th e rm a l u n its ab so rb ed w ill be 388 p e r pound of d u st. D ry g y p su m co n ta in s 21 p e r cen t o f w a te r o f c o n s titu tio n w hich, a t as low a te m p e ra tu re a s 250 deg. F ., b e g in s to be expelled. L et us assu m e t h a t th e w hole o f th e w a te r p f c o n stitu tio n is d raw n off a t 250 deg. F . T h en th e h e a t ab so rb ed in B r itis h th e rm a l u n its w ill b e : 47 in r a is in g th e te m p e r a tu r e o f th e g y p su m to 250 deg. F ., 48 in decom posi
tion, 203 in ev ap o ratio n , 237 in h e a tin g th e calcium s u lp h a te to th e te m p e r a tu r e of 1,832 deg. and 166 in r a is in g th e ste a m to th e sam e te m p e r a tu r e — a to ta l of 701 B .t.u.
L im esto n e h as also been re g a rd e d w ith fa v o r. Does n o t lim esto n e also b re a k up u n d e r h e a t? U n fo rtu n a te ly th e te m p e ra tu re a t w hich th a t d isso c iatio n occurs is so
w ith a sto k e r a n d t h a t a b o u t 25 p e r c e n t less coal w ould
• be needed fo r th e sam e p u rp o se. T he sto k e r w ould also be m ore flexible, ra is in g th e te m p e ra tu re ra p id ly if d esired and h o ld in g t h a t te m p e ra tu re a t a n y level w hich m ig h t seem n e cessary . W ith su ch a m ech an ism f o r con
tin u o u s fe e d in g i t w ould be possible to elim in a te sm oke w hen b u rn in g th e sm o k iest o f fuels.
M r. H e rre s sa id th a t th e Pacific C oast Coal Co. h a d a sm all sto k e r fu rn a c e th a t w as m o re sim ple th a n th e H a rrin g to n . P u lv e riz e d coal eq u ip m en t w as b e in g ad a p te d to use in a p a r tm e n t houses. Two o th e r sto k e rs w ere m entioned, one developed, b u t n o t b ein g com m er
cially m a n u fa c tu re d , by M r. G a rriso n , th e s ta te e n g i
n e e r of U ta h , w ho re sid e s in S a lt L ak e C ity, an d one w hich M r. M ag ea th , of O m aha, N eb., h a s been m a n u fa c tu r in g . M r. M cA uliffe sa id t h a t M r. M ag eath recom m ended h is sm all u n it only f o r Rock S p rin g s coal.
A s h o rt discu ssio n on ro ck d u s tin g follow ed, M r.
H a rrin g to n d e clarin g t h a t n e a rly all th e o p e ra to rs w e re d u stin g to o lig h tly f o r sa fe ty . W ith U ta h coal i t w as n ec essary to have th e d u s t in th e ro ad w ay s 75 p e r cen t in e rt m a tte r. R. M. M a g ra w s ta te d t h a t on in q u iry a t th e B u re a u of M ines he h ad been told th a t ab o u t 5 to n s o f d u st should be used f o r 1,000 tons* o f o u tp u t.
g r e a t th a t i t is d o u b tfu l if th e actio n ev er ta k e s place d u rin g an explosion a n d m uch m ore d o u b tfu l w h e th e r, if i t should occur, i t w ould p ro g re ss in a n y g r e a t m eas
u re. O nly a t 1,700 deg. F . an d u n d e r exceptionally fa v o ra b le c irc u m sta n c es does th e lim esto n e b e g in to lose carb o n dioxide. P r io r to th a t tim e 352 B .t.u . a re ab so rb ed , th e decom position adds to th is 765 B .t.u . and th e h e a tin g of th e p ro d u c ts to 1,832 deg. F . adds to th e h e a t a b so rp tio n 30 B .t.u., m a k in g a to ta l of 1,138 B .t.u.
T h is is an im p re ssiv e fig u re 1,138 as a g a in s t 388 f o r th e indecom posable bodies a n d 701 fo r gypsum .
M r. J u d d believed, how ever, t h a t u n d e r a c tu a l con
d itio n s th e lim esto n e w ould a b so rb no m ore h e a t th a n any indecom posable d u s t such as silica sand, leu cite or shale and th a t g y p su m w as th e m ore d esira b le m a te ria l.
G ypsum m ig h t m ake ideal ta m p in g . T h e e x p e rim e n ts b ein g m ade by J . K. M abb^ up to th e p re s e n t show ed th a t g y p su m w a s by f a r th e le a s t a b so rb e n t of m o is tu re of any of th e in e r t bodies te ste d , t h a t lim esto n es v a rie d g re atly , som e b e in g slig h tly m ore a b so rb e n t th a n g y p sum an d som e f a r an d aw ay m o re ab so rb e n t. S ilica sand w as q u ite h ig h ly disposed to ta k e up m o istu re .
On F r id a y m o rn in g a p a p e r on “ D om estic F u el S to k ers,” w r itte n b y Jo sep h H a r r in g to n , w as re a d by th e s e c re ta ry o f th e I n s titu te , B e n ed ict S h u b a rt. T he a u th o r .asserted t h a t m uch c h eap er coal could be used
T. C. H a rv e y th e n re a d a b r ie f d esc rip tio n of th e Co
lum bia tip p le an d m ine. T h e s e c re ta ry announced th a t d e to u rs h ad been a rra n g e d aro u n d th re e b a d w a sh o u ts betw een C olum bia a n d P ric e an d t h a t c a rs w ere re a d y to tak e th e v is ito rs to th e fo rm e r place w h e re an elab o ra te luncheon h a d been p re p a re d by th e C olum bia S teel Co. A t th is m in e all th e coal w as b e in g cru sh ed , th e p icking tables n o t b e in g in o p e ra tio n w hen th e v is ito rs w en t th ro u g h th e tip p le. T h e coal a t th is m in e a n d a t S un n y sid e does n o t hav e a n equal q u a n tity o f re sin w ith th a t of H ia w a th a a n d S p rin g C an y o n ; in f a c t i t is believed by som e to be p a r t o f a d iffe re n t seam . A f te r lunch th e autom obiles re tu r n e d to P ric e a f t e r a s h o rt v isit to th e h is to ric tip p le a t S u n n y sid e.
On one occasion w hen th e S u n n y sid e tip p le b u rn e d , th e sm elters o f alm o st th e e n tire W est w e re d ep riv ed o f fuel. Ten days a f t e r th e fire th e tip p le w as re-e re cte d and w as c ru s h in g coal a s m e rrily as ever, th e D e n v er &
R io G rande R.R. h a v in g d is ru p te d its serv ic e to g e t th e m a te ria l fro m S a lt L ak e C ity to S u n n y sid e. On a n o th e r occasion a shovel g o t in to th e d is in te g r a to r an d th e sp a rk s th a t re su lte d th o u g h m erely th e re s u lt o f m echanical violence serv ed to explode th e d u st. E v i
dences of th e b u rn in g o f th e shales due to th e crop fires in th e coal should be seen n e a r th e tip p le. T h is w as th e I n s titu te ’s la s t m in e v isit.
Jfy West Tries Everything in Rock Dusting
B y D . H arrington
C o n s u l t i n g 1 E n g i n e e r p S a l F L a k e C i t y , U t a h
P
R A C T IC A L L Y every m ethod o f rock d u s tin g coal m ines is now used in th e Rocky M o u n tain s ta te s.E x p e rien c e and s tr ic t m in in g s a fe ty law s hav e d riv e n m in in g m en to th is fo rm of explosion p re v e n tio n — and m ost of th em a re convinced w a te r is also a n ece ssa ry s a fe g u a rd . T hey have tr ie d all th e d u s tin g processes know n an d i t is in te re s tin g to n o te t h a t th e m o st suc
cessfu l have tu rn e d c lear back to th e p ra c tic e o f 1916 a s i t w as developed, b e g in n in g in 1912, a t th e D elag u a m ine o f th e V ic to r-A m e rican F u e l Co. in Colorado.
T h is w as th e firs t extensively ro ck -d u sted coal o p e ra tio n in th is co u n try .
In 1916, w hile in th e B u re a u o f M fnes serv ice, I m ade an u n d e rg ro u n d stu d y a n d a r e p o r t to th e B u re a u on th is m ine. T h e re w ere th e n som e 10 m iles o f e n try in th a t m in e w hich h a d been k e p t w ell ro ck d u ste d f o r a t le a s t fo u r y e a rs. T he d u st u sed w as “ adobe”
o r su rfa c e soil screened fro m sw eep in g s of th e d ry su rfa c e w agon ro ad s th ro u g h a screen w ith ¿-in. open
in g s, th e d u st g iv in g a b o u t 20 p e r c e n t th ro u g h 200 m esh and ab o u t 10 p e r c en t of a p p ro x im a te ly J in. size.
T h e m a te ria l w as collected d u rin g d ry w e a th e r by con
tr a c t a t $1 p e r to n (sack ed ) an d w as a c c u m u lated in su m m er and sto re d f o r w in te r an d s p rin g use.
T he d u s t w as sc a tte re d th ro u g h h a u la g e e n trie s by h a n d o r by a n ele ctrically o p e ra te d blow er an d w as held on shelves along th e r ib s o r betw een and on tim b e r caps w ith fro m \ in. to 2 in. th ic k n e ss o f th e ro ck d u st.
T h e cost o f m a in ta in in g th e 10 m iles o f e n tr y w ell d u sted w as a b o u t $1,500 p e r y e a r or $150 p e r m ile p e r y e a r. T o tal cost of th e ro ck d u s tin g over a fo u r-y e a r p erio d w as a b o u t $6,000, a b o u t 2,500 to n s o f d u st b ein g used a n d 2,000,000 to n s o f coal p roduced. T he cost included a b o u t 1,200 d ay s lab o r d u s tin g a t $2.50 p e r day, 2,500 to n s of ro ck d u s t a t $1 p e r to n an d m iscellaneous labor, m a te ria l, r e p a irs , p o w er cost, etc.
a m o u n tin g to ab o u t $500. T he cost p e r to n o f coal p roduced f o r k eep in g 10 m iles o f e n try ro ck d u ste d w as a b o u t 0.3c.
Sp r i n k l e d In t e r i o r o p Mi n e
In a d d itio n to th e rock d u stin g , som e s p rin k lin g w as done chiefly in th e in te r io r of th e m in e c o stin g a b o u t 0.4c. p e r to n ; and, due to sp illin g o f coal a n d s if tin g of coal d u st th ro u g h loose ca rs on th e e n try floors, th e floors of h a u la g e ro ad s w e re k e p t sp rin k le d betw een an d ju s t o u tsid e th e ra ils. T o tal cost o f sp rin k lin g and rock d u s tin g w as a b o u t 0.7c. p e r to n , m u ch less, of course, th a n th e sam e w ork w ould now cost.
T he D olom ite explosion n e a r B u rm in g h a m , A la., in N ovem ber, 1922, an d th e D aw son No. 1 M ine explosion a t D aw son, N . M., in F e b ru a ry , 1923 ( a t b o th o f w h ich I m ade u n d e rg ro u n d in sp ectio n s a n d r e p o r ts ) b o th s ta r tin g on m ain in ta k e h a u la g e ro a d an d b o th in m in es w hich h a d f a ir ly ela b o ra te w a te rin g sy stem s, con
vinced m e t h a t a t le a s t as f a r as fre e z in g can occur on m a in in ta k e a ir courses w hich also a c t a s m a in h a u la g e - w ays, rock d u stin g is likely to be m uch m ore dependable th a n sp rin k lin g .
T h i s a r t i c l e is f r o m a p a p e r r e a d b y M r. H a r r i n g t o n a t t h e P r i c e m e e t i n g o f t h e R o c k y M o u n t a i n C o a l M i n i n g I n s t i t u t e , A u g . 24, 1925.
In m a k in g up th e re p o rt on th e D aw son explosion to th e B u re a u of M ines (copy o f w h ich also w e n t to th e ow ners of th e D aw son p ro p e rtie s ) I s tro n g ly u rg e d th e rock d u s tin g o f m a in in ta k e -m a in h a u la g e ro a d s (of w hich th e r e w ere m an y m iles b e in g o p e ra te d a t D aw son) a t le a s t a s f a r as fre e z in g ex ten d ed in coldest w e a th e r to g e th e r w ith e x ten sio n o f w a te rin g m eth o d s in th e in te r im m in e w o rk in g s p lacin g w a te r lines, and w a te r hose a t e v e iy w o rk in g face,, a n d keep in g th o ro u g h ly w et all open in te r io r w o rk in g s. T he use o f w a te r on c u ttin g ch a in s on all m in in g m ach in es and also th e s p rin k lin g o f loaded c a r to p s a t th e faces an d on p a rtin g s w as recom m ended. I t w as s tro n g ly recom m ended th a t each sectio n o f all m in es be p ro te c te d by ro ck -d u st b a r r ie r s .
Mo st Mo d e r n Pr a c t ic e s a t Da w s o n
B y J a n u a r y , 1924, o r a b o u t a y e a r a f t e r th e D aw son No. 1 explosion, th e D aw son m in es w ere by all odds th e m o st u p -to -d a te m in es I h a d e v er seen fro m th e sta n d p o in t o f h e a lth a n d s a f e ty ; b o th rock d u s tin g a n d w a te rin g m eth o d s w e re b e in g used to an e x te n t w h ich I h a d n e v e r b e fo re en co u n tered . T h e D aw son m in es quickly becam e th e m ecca of w e s te rn coal m in in g people an d alm o st im m e d iately m odifications of th e D aw son p ra c tic e w e re b e in g ad o p ted in m in e s of N ew M exico, Colorado, U ta h a n d W yom ing.
T h e now fam o u s U ta h re g u la tio n s ad o p ted a f t e r th e C astle G ate explosion in M arch , 1924, in v olving com
p u lso ry ro ck d u s tin g “a t le a st in to th e m o st d is ta n t p o in ts w h e re fre e z in g ta k e s place in coldest w e a th e r,”
use of rock d u s t b a r r ie r s , u se o f w a te r on co a l-c u ttin g m achines, com pulsory sp rin k lin g of fa ces b y m in e rs and o f all o th e r in te r io r open w o rk in g s by th e com pany, exclusive use of p e rm issib le explosives a n d o f e le ctric b la s tin g an d exclusive use o f closed lig h ts , a r e all D aw son p ra c tic e th o u g h som e o f th e se p ra c tic e s h a d th e ir o rig in in U ta h a n d som e w ere in a t le a s t p a r tia l use p rev io u sly in U ta h m in es as well a s in m in es of N ew M exico, C olorado an d W yom ing.
W hile all o f th e U ta h coal o p e ra to rs a g re e d to th e new re g u la tio n s b e fo re th e y w e re issu ed som e have been so m ew h at d o u b tfu l as to th e efficiency of ro ck d u stin g , y e t p ra c tic a lly all a re in som e d eg ree com
p ly in g w ith th e law . Som e o f th o se a t firs t fra n k ly sk ep tical now a r e ro ck d u s tin g f a r beyond th e a m o u n t specified in th e n ew re g u la tio n s ; som e a re ro ck d u s tin g as specified by th e new re g u la tio n s o r even beyond th e d em and of th e re g u la tio n s a n d a r e sim u lta n e o u sly s p rin k lin g in te n siv e ly th e floor of th e places w h e re rib s, ro o f a n d floor a re ro c k d u ste d an d a re so a kin g th e in te r io r m in e w o rk in g s. On th e o th - r h an d , th e r e a re a fe w w hose ro ck d u s tin g is ev id en tly done only to
“g e t b y ” w hen th e s ta te in sp e c to r com es a ro u n d .
One o f th e m o st ex ten siv ely ad o p ted a d ju n c ts to ro ck d u s tin g in w e ste rn m in es is th e s p re a d in g on th e floor o f in ta k e h a u la g e e n tr ie s o f s u rfa c e soil or adobe w h ich u su ally becom es d ry an d d u sty and, in a d d itio n to g re a tly a id in g in tr a c k b a lla stin g , also sen d s in to th e a i r by m ovem ent o f a n im a ls, tr ip s , etc., co n sid erab le q u a n titie s o f finely divided in co m b u stib le d u s t w h ich
Se p t e m b e r 3, 1925 C O A L A G E 311
a w atery m u d of a b o u t 20 p e r ce n t solids and “m u d itin g ” or covering roof, rib s, an d floor w ith th e w a te ry m ud w hich h a s som e decided a d v a n ta g e s in p r o te c tin g an d covering exposed su rfa c e s. W ith c e rta in k in d s of soil and a f te r successive c o a tin g s in places w hich d ry o u t rap id ly , th e d rie d “m u d ite ” acts la rg e ly a s o rd in a ry rock d u stin g .
Some sm aller m in es apply ro ck d u s t b y h a n d b u t m ost of th e com panies have m ade th e ir own ro ck d u s te rs and, curiously enough, m o st o f th e ro ck d u s tin g m a chines a re essen tially m odelled a f t e r th e one used by th e V icto r-A m e rican F u el Co. a t D elagua, Colo., in 1912 to 1916. T h ese m ach in es c o n sist o f a sm all, electrically-driven, belt-connected blow er ( h e a te r gag e 2 to 5 in.) and a d u st h o p p e r w ith a n o u tg o in g pipe.
Locally-m ade m ach in es o f th is ty p e co st so m ew h at less th a n $1,000 an d some of th e m d u s t 25 to 35 lin .ft. of e n try p e r m in u te . One such m ach in e re c e n tly re d u ste d 17,000 f t. of e n try a v e ra g in g 10x12 f t. in cro ss-sectio n in e ig h t sh ifts .
Cost of rock d u s tin g b y th e se blow er u n its , u sin g crushed lim estone o r cru sh ed leucite, ru n s fro m 2 to 4c.
p e r foot of e n tr y ; a b o u t 60 p e r c e n t is labor, 30 p e r cen t rock d u st an d a b o u t 10 p e r c e n t m iscellaneous ite m s such as pow er a n d m a te ria ls used. T h e a m o u n t of
Typical U tah Incline
T h e s e a m m i n e d b y t h e C a r b o n F u e l G o . a t R a i n s o u t c r o p s h i g h o n t h e f a c e o f t h e h i l l , m a k i n g n e c e s s a r y t h i s l o n g c o n v e y o r t o t h e t i p p l e a n d l o a d i n g p l a n t . R . P . F i t c h i s s u p e r i n t e n d e n t o f t h i s m in e . H i s t o p p l a n t , a s w e l l a s s e v e r a l o t h e r s i n U t a h , i s c a p a b l e o f a p p l y i n g m o s t o f t h e r e f i n e m e n t s n o w k n o w n in c o a l p r e p a r a t i o n . S o m e I T ta h o p e r a t o r s d e p l o r e t h i s r e c e n t d e v e l o p m e n t o f s i z e - i n g t h o u g h i t m a k e s t h e c o a l o f t h a t s t a t e e v e n m o r e m a r k e t a b l e .
u ltim a te ly s e ttle s on rib s, tim b e rs , ro o f, etc., a n d aid s in k e e p in g p e rc e n ta g e o f co m b u stib le low.
D u rin g th e p a s t y e a r o r y e a r an d a h a lf m u ch over a h u n d re d m iles o f h a u la g e e n try floor in w e s te rn coal m in es have been covered w ith fro m a fe w in ch es, to a s m uch a s a fo o t o f soil o r adobe a t a co st o f fro m 10c. p e r fo o t of e n tr y to 25c. o r even m ore, d e p en d in g upon th ic k n e ss o f th e co v erin g , a m o u n t o f p r e p a ra to ry c le a n in g done an d w h e th e r th e adobe can be fo u n d re a d ily a v a ilab le to th e m ine, w h e th e r it can be loaded in p it c a rs by ste a m shovel o r by h o rse sc ra p e r a n d tr a p o r by h an d , etc.
S u ita b le m a te ria l f o r th e floor c o v e rin g is alm o st a n y th in g w hich p u lv erizes upon becom ing d ry , a n d h a s a com bustible c o n te n t o f less th a n 10 p e r cen t. In m a n y in sta n c e s th e m a te ria l h a s over 50 p e r c e n t fre e s ilic a b u t no a la r m is f e lt since little o f th is m a te ria l g e ts in to th e a ir b re a th e d b y w o rk e rs a n d up to d a te no c o m p lain ts hav e been m ad e n o r h a s th e r e been a n y evidence o f tro u b le . W hile placed in m in es in lum ps a s la rg e a s a m a n ’s head th is m a te ria l d rie s a n d d is
in te g ra te s to su ch a n e x te n t t h a t w h en sam pled on e n try floors a f t e r a fe w m o n th s o f serv ice i t ru n s 25 to 50 p e r c e n t th ro u g h a 200-m esh screen.
F o r o rd in a ry ro ck d u s tin g p u rp o se s th e m a te ria l m o st
in use in th e W e st is c ru sh e d lim esto n e o b tain ed fro m cem en t m ills o r sm e lte rs a t a cost of $3 to $5 p e r to n sacked a t th e m ill o r sm elter. F in e n e ss is 40 to 60 p e r c e n t th r o u g h 200 m esh. F r e ig h t b rin g s th e cost, f.o.b. m ine, to $5 o r $5.50 an d in a t le a s t one in sta n c e to $8 p e r to n . A fe w m in e s in U ta h h av e used cru sh e d leu cite w h ich is silv e ry w h ite in color a n d g liste n s b rillia n tly w hen c ru sh e d to 100-m esh o r less, is alm ost e n tire ly in co m b u stib le, co sts a b o u t th e sam e as th e c ru sh e d lim estirhe a n d is placed on th e rib s, ro o f, etc., a lm o st a s re a d ily a s lim estone.
B o th th e c ru sh e d lim esto n e an d th e c ru sh e d leucite a b so rb m o is tu re in h u m id a ir . . A fe w m in es a re p re p a rin g to c ru sh t h e i r own local m a te r ia l an d a t le a st one com pany in C olorado h a s a com bined c ru s h e r and rock d u s te r w h ich co n v e rts sh ale u n d e rg ro u n d to d u st a n d im m ed iately d e p o sits it. T h is com pany ro c k d u sts all open p a r ts of th e m in e up to and in c lu d in g th e fac es. A fe w m ines, a r e c o n v e rtin g local sh ale oil to
d u st deposited on rib s an d ro o f ru n s 2 lb. o r less p e r fo o t o f e n try . M any o f th e U ta h m in e s h av e used com pressed a i r on a n in je c to r p rin c ip le fo rc in g rock d u st a g a in s t r ib s o r ro o f w ith a h ig h velocity propelled by com pressed a i r a t 40 to 70 lb. p e r sq u a re inch. T h is so-called h ig h -p re s s u re d u s tin g d islodges coal d u st fro m crevices, ledges and o th e r p ro je c tio n s an d leaves a p la s te r of J to i in. of ro ck d u s t upon rib s , ro o f, tim b e rs, etc.
T he m in in g com panies o f U ta h p ra c tic a lly all h av e a i r com pressors, s ta tio n a r y o r p o rtab le, an d w a te r lin es (now u n iv e rsa l in U ta h m in e s) c an be used fo r c a rry in g com pressed a i r a n d as a re s u lt th e h ig h p re s s u re d u s tin g is p o p u la r b ecause i t leaves a h e a v ie r c o a tin g o f d u st th a n o th e r m eth o d s (3 to 6 lb. p e r fo o t o f e n tr y ) an d co sts b u t little m ore th a n w ith th e lo w -p ressu re m e th ods. C osts r u n fro m 4 to 6c. p e r lin eal fo o t of e n try .
M any U ta h o p e ra to rs now believe th e firs t co atin g o f ro ck d u s t should be m ad e b y th e h ig h -p re s s u re
312 C O A L A G E Vo l. 28, No. 10
m eth o d w ith su b se q u en t o r re d u s tin g coats, w hich re q u ire b u t 1 to 2 lb. p e r fo o t of e n try , to be done w ith lo w -p ressu re m ach in es w hich a re so m ew h at th e quicker.
One U ta h m ine now figures on p lacin g ro c k -d u st boxes along m in e w o rk in g s ab o u t every 500 f t. an d u sin g th e com pressed a ir th ro u g h w a te r lin es to fo rc e th e rock d u st in to th e a ir to be la te r deposited by th e a ir on roof, rib s and floor an d i t is expected to be able to rock d u st p ra c tic a lly all in ta k e a ir co u rses of a f a ir ly la rg e m ine (c a p a c ity 2,000 to n s p e r d a y ) in a b o u t tw o s h ifts . A n o th er m in e now h a s a n effective d u stin g m achine of th e u su al blow er ty p e b u t ta k in g its pow er fro m th e w heels of a p it c a r w h ich m ay be h au led by a m ule. I t is now fe lt by m an y U ta h coal m in in g m en th a t w here a ir velocity is a s h ig h as 500 f t. p e r m inute, re d u s tin g can be done re a d ily b y u s in g th e a i r c u rre n ts as d is trib u to rs . T he d u st is th ro w n in to th e a ir by blow er a t p o in ts 500 to 1,000 f t. a p a rt.
H ow ever, o th e r o p e ra to rs sa y t h a t u sin g a ir c u r re n ts to d is trib u te rock d u st beai-s th e sam e re la tio n s h ip to efficient rock d u stin g as do fro zen w a te r lin es to effi
cie n t sp rin k lin g m ethods.
Rock d u st b a r r ie r s used in th e W est a re la rg e ly of th e V -tro u g h ty p e u sin g 16 to 20 tro u g h s in a b a r r ie r , th o u g h some m ines w ith h ig h coal use 30 o r m ore tro u g h s p e r b a rrie r. T he volum e o f ro ck d u s t p e r b a r r ie r ru n s fro m 2,500 to 5,000 lb. V a rio u s k in d s of ro ck -d u st m a te ria l a re used in th e se b a r r ie r s , a m o n g th em cru sh e d lim estone, cru sh ed leucite, siliceous m ill ta ilin g s, adobe, flue d ust, etc. I t is f e lt t h a t alm ost a n y k in d of fine incom bustible m a te ria l w ill se rv e p r o vided its specific g r a v ity is n o t too g r e a t a n d pro v id ed
I t is fo u n d t h a t in th e e x trem ely h u m id a ir o f m ost o f o u r U ta h m in e s w h ich use w a te r fre e ly in in te r io r sp rin k lin g , th e lim estone, leucite, flue d u st, an d som e adobes ab so rb so m uch m o istu re as to becom e a p a ste
• or m u d un less secu rely covered by som e such im p erv io u s m a te ria l a s oil cloth. H ig h ly siliceous m a te ria l, how ever, a b so rb s little o r no m o is tu re an d i t now a p p e a rs th a t cru sh ed q u a rtz w ould be a d m ira b le m a te ria l f o r ro ck -d u st b a r rie rs .
T he u su a l 16- to 2 0 -V -tro u g h b a r r ie r c o n stru c te d of tim b e r costs $50 to $75 com pletely installed , w hile th e sam e k in d of b a r r ie r c o n stru c te d of g alv an ized iro n tro u g h s an d s im ila r m a te ria l, such a s is now u sed to a co n sid erab le e x te n t by one com pany, co sts a ro u n d
$100. In m y opinion th e u se of g alv an ized iro n o r s im ila r m a te ria l f o r p e rm a n e n t b a r r ie r s is th e w ise;-, and in th e long ru n th e cheaper, as th e w ooden b a r r ie r s soon becom e deform ed, o r th e y decay, or th e y sw ell d ue to m o istu re and can be re lie d upon to re m a in in good w o rk in g co n d itio n b u t little over a y e a r in m o st places and m uch less th a n a y e a r in m an y places.
Some m in es usé a succession of co m p a ra tiv e ly loose shelves as b a r r ie r s , th e shelves e x te n d in g p ra c tic a lly across th e opening, w h e re th e r e is no h au lag e, o r along th e rib w h e re th e r e is h a u la g e ; som e p ro p e rtie s use as b a r r ie r s a supply o f ro ck d u s t co n ta in e d in a p e r p e n d ic u la r box-like o p en in g in th e rib held in place by a door w hich is opened by a vane-like tr ig g e r e x te n d in g in to th e m in e opening. A fe w m in es a r e p re p a rin g to use th e c o n c e n tra te d ty p e o f b a r r ie r recom m ended by th e B u re a u o f M ines. Som e m in es h av e w ell over 100 b a r r ie r s in stalled , th o u g h in g e n e ra l n o t m o re th a n 15 to 25 b a r r ie r s a re fo u n d in a n y one m in e an d m o st m ines hav e o m itte d th e b a r r ie r s wholly.
It
^ilso th a t it will n o t pack or consolidate too m u ch o r th a t it. will n o t ab so rb m o istu re to too g r e a t an e x te n t.
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U ftE A U O F M IN E S T echnical P a p e r 172, by S. H.K atz an d H. C. P o rte r, e n title d “ E ffects of M ois
tu r e on th e S po n tan eo u s H e a tin g of S to re d Coal” say s a t th e o u tse t, “ S po n tan eo u s fires in s to ra g e p iles of b itu m in o u s coal hav e been th e so u rce o f tro u b le an d loss since th e in d u s tria l u tiliz a tio n of coal b egan. In E u ro p e th e id e a - aro se t h a t sp o n tan eo u s com bustion is m ore liable to h appen d u rin g w et w e a th e r th a n d u rin g dry. S ta te m e n ts fa v o rin g o r opposing th is idea have c re p t in to th e lite r a tu re . C onflicting conclu
sions, based on ex p e rim e n t as well as opinions b ased on o b serv atio n s of v a rio u s d eg rees of re lia b ility , a re g iv en in m ost of th e recorded d iscussions of th e su b je c t.
“B ecause of th e u n c e rta in ty of th e effect o f m o istu re an d its seem ing im p o rtan ce am ong th e co n d itio n s th a t effect sp o n tan eo u s com bustion in sto re d coal, th e w ork d escribed in th is p a p e r w as u n d e rta k e n by th e B u re a u o f M ines. T he ex p erim en ts show ed th a t a coal fro m Illin o is oxidized f a s te r w hen dry, w h ereas a sam ple of P itts b u r g h coal oxidized f a s te r w hen m oist. T h ese d is
c o rd a n t re s u lts an d sim ila rly in c o n siste n t re s u lts fro m th e o b serv a tio n s o f d iffe re n t in v e s tig a to rs m a y be coupled w ith th e fa c t th a t u n d e r a c tu a l c o n d itio n s of s to rin g , b o th coal an d a ir alw ays co n tain a co n sid erab le am o u n t of m o istu re .”
T h i s a r t i c l e is f r o m a p a p e r p r e p a r e d b y M r. C r a w f o r d f o r t h e P r i c e m e e t i n g o f t h e R o c k y M o u n t a i n C o a l M i n i n g I n s t i t u t e .
T he fo re g o in g r e p o rt of th e in v e stig a tio n s of th e B u re a u d e m o n stra te s t h a t th e m y s te ry o f sp o n tan eo u s com bustion h a s n o t y e t b een solved.
I becam e in te r e s te d in th e m a tte r a b o u t te n year's ago in o b serv in g w h a t w as p ro b a b ly one of th e b e s t ex h ib itio n s o f th is phenom enon. T h e old dum p a t C astle G ate No. 1 m in e co n ta in e d bony coal an d tr a c k clean in g s ge n era lly . In w in te r w hen snow fell upon th is old dum p, th e snow w as soon m elted b y th e h e a t of th e dum p w h ic h w as co m p a ra tiv e ly w a rm a t all tim es. W ith in 48 h r. a f te r w a r d little blue flam es w ere in evidence on th e s u rfa c e o f th e pile. F e w of th e gas fe e d e rs w ere sufficiently c o n s ta n t to m a in ta in a ste a d y flame a t a n y g iv en p o in t, b u t s h if tin g em issio n s o f g as w ere ig n ite d one b y a n o th e r, re s u ltin g in a c o n tin u o u s p opping an d a p p a re n t r u n n in g a b o u t o f th e flam es.
A n o th e r in te r e s tin g e x h ib itio n o f sp o n tan eo u s h e a t
in g w as to be seen a fe w y e a rs ago in th e s to ra g e coal piles of th e local s u g a r fa c to rie s. T h is coal w as p iled in co n crete lin ed p its filled w ith w a te r. H ow ever, on th is occasion th e coal ex ten d ed above th e su rfa c e o f th e w a te r. A t every p la n t w h ere th is co n d itio n e x isted th e coal w as soon h e a tin g , an d in each case th e affected a re a w as in a p lane h o riz o n ta l to a n d fro m 8 to 14 in.
above th e w a te r level. T he h e ig h t o f th e h o t a r e a above th e su rfa c e of th e w a te r a p p e a re d to be affected by th e fineness o f th e coal.
