Enumeration of bacteria in soak w aters [for anim al skins]. G. E. R o c k w e l l (J. Amer. Leather Chem. Assoc., 1931, 26, 2—7).—The soak water is agitated from the bottom up with a plunger, and samples of the plunger liquor and soaked skin are collected immediately in a sterile jar, which is then revolved in a shake machine for 10 min. Dilutions of 1 :10—1 : 106 are then prepared and 1 c.c. of each of a suitable range of dilutions is plated on a meat extract-agar medium adjusted to + 0-5 on the Fuller scale, in a Petri dish.
Three dilutions are usually necessary for each co u n t;
the range chosen depends on the character of the soak water, but should be such as to give 50—150 colonies on incubation. When the medium has set, the plates are incubated for 24 hrs. at 37° and for 24 Ins. a t room temperature. Plates with 50—150 colonies are then counted and the number of bacteria per c.c. of original soak water is calculated therefrom. D. W o o d r o f f e .
Quick tannage. M. B e r g m a n n , W. M u n z, and L. S e l i g s b e r g e r (Collegium, 1930, 520—524).—The speed of penetration of 1—5% solutions of commercial N eradolN D and of pure naphthalene-1-and-2-sulphonic acids, respectively, was determined on hide pieces. The penetration of the sulplionic acid was greatest for the last-named compound. By determinations of the swelling and the imbibed water it is deduced th a t the hide capillaries are enlarged by the above products and the hide is rendered thicker, less compressible, and more distended. The hide is similarly affected by other acid solutions of similar p n value, but these diminish the porosity of the hide. Tannage can be accelerated by substances which will disperse the tanning materials or by sulplionic acids which increase the porosity and penetrability of the pelt. D. W o o d r o f f e .
Qualitative analysis of tannins. [Report of a C om m ittee of the Internat. Verein der L eder-Ind.- Chemiker.] 0 . Gerngross (Collegium, 1930, 524—
532).—Mixtures of quebracho and sulphite-cellulose waste extracts were tested for sulphite-cellulose by means of the Procter-Hirst, cinchonine, and fluorescence reactions. As little as 4% of sulphite-cellulose in the mixture could be detected by the Procter-H irst reaction, b u t 5% was required to show a positive reaction with the other tests. A positive test was shown with sulphited quebracho by all three reactions, bu t by the Procter- H irst and cinchonine reactions the test was positive only with an extract prepared by sulpliiting the insoluble m atter in a quebracho extract. Publications on quali
tative analysis are reviewed for the last two years.
D. Woodroffe. Sedim ent in tanning extracts. W . V o g e l (Gerber, 1930, 56, 129—132 ; Chem. Zentr., 1930, ii, 2600).—The sediment in tanning extracts (d up to 1 • 107) was deter
mined by Kubelka and Nemec’s method. Different portions from the same material differ as regards th e am ount of sediment formed and its dependence on the concentration. The determination of insoluble m atter in tanning extracts is not a measure of the am ount of deposit formed in practice.. A. A. E l d r i d g e .
Leather for g as-m eters. An d r e w s.—See II.
Pa t e n t s.
T annage of ch am ois, buckskins, or other leath er.
A. Er n s t (U.S.P. 1,771,490, 29.7.30. Appl., 8.5.28).—
The limed, washed, and pickled skins are treated with formaldehyde for 45 min., then an emulsion of degras- in soap and soda is added to the formaldehyde bath, and the treatm ent is continued till the skins are tanned.
D . Wood ro ffe. Manufacture of gelatin products. 0 . H a a v a r d s -
holm (U.S.P. 1,770,573, 15.7.30. Appl., 30.6.28. Ger.
and Norw., 7.5.28).—Gelatin is granulated or pulverised, the crumbs are stored in an atmosphere of 60—70%
R.H. and a t 21—27°, then compressed a t 20,000—
30,000 lb./in.2 into tablets, and these are subjected to- the action of wet steam and rapidly dried.
D. Wood roffe. P la stic casein com position. J. G. D a v id s o n and E . W . R e id , Assrs. to C a r b id e & C a rb o n C h e m ic a ls C orp. (U.S.P. 1,772,131, 5.8.30. Appl., 3.1.28).—
Casein is mixed with 5% of water and triethanolamm&
or a m ixture of “ ethanolamines.” D . W o o d r o f f e .
B ritish C h em ica l A b s tr a c ts — B .
O l. X V I.— AaiuouLTü'Rji. 311
T ar-rem oval from leather (B.P. 338,167).—See II.
Azo dyes for leather (B.P. 338,930 and 339,029).—See IV. D yeing of sk in s etc. (B.P. 339,444).—See VI.
X V I.— AGRICULTURE.
Tropical s o ils. I. Identification and approxi
mate determ ination of sesq u ioxid e com ponents by adsorption of alizarin. F. Ha r d y (J. Agric. Sci., 1931, 21, 150—166).—Free alumina in clays and soils absorbs alizarin only after ignition, whereas free ferric oxide absorbs it only in the fresh unignited state. A method of determining the sesquioxides is based on this difference (cf. Schmelev, B., 1928, 895). Examination of numerous soils and their clay fractions is recorded.
In most cases the amounts of free alumina present were small and only moderate proportions of iron occurred as the free hydrated oxide. Of the materials examined bauxite and laterite contained the largest proportions of free oxides. The clay fractions of soils contained rather less free alumina but more free ferric oxide than the whole soils. A. G. Po l l a r d.
Electrical conductivity of aqueous so il su sp en sions a s a m easure of so il fertility. A. Se n and C. II. Wr ig h t (J. Agric. Sci., 1931, 2 1 , 1—13 ; cf. B., 1928, 870).—The electrical conductivity of soil suspen
sions and the “ 7-days’ increase ” (increase in conduc
tivity after storage of suspension for 7 days a t 25°) for a number of soils are recorded. The initial conduc
tivity of an unmanured soil under continuous cropping steadily decreases, reaching a value which remains constant for many years. Continuously manured soils show a sim ilar decline (except for tem porary increases following applications of manures), reaching a constant value slightly higher th an th a t of corresponding un
manured soils. The “ 7-days’ increase ’’ also becomes steadily smaller in both manured and unmanured soils, the decrease in the latter case being notably rapid in the early years of continuous cropping. The 7-days’
increase for manured soils is consistently higher than that of the unmanured, dung producing greater differ
ences th an those given by artificial fertilisers. The 7-days’ increa.se is closely correlated w ith the crop yield. An impoverished soil allowed to “ run wild ” shows a steady rise in the initial conductivity and the 7-days’ increase. Prolonged storage of air-dry soil does not appreciably affect the initial conductivity, but the 7-days’ increase rises rapidly to a fairly constant value in the first few months of storage. A. G. Po l l a r d.
“ S tick y-p oin t ” w ater of so ils. B. d e C. Ma r-
chand (S. Afr. J. Sci., 1930, 27, 183—193).—The water content, by vol., of soil a t the “ sticky point ” is deter
mined by weighing a block of soil a t the sticky point in water and in xylene. From values so obtained the water capacity, pore space, and clay content are cal
culated. Sticky-point moisture was closely correlated with the clay content of soils, bu t not w ith the “ loss on ignition.” The sticky-point water of soils examined was closely related with the water capacity (cf. Keen and Raczkowski, B., 1922, 70 a), bu t yielded values of approximately two thirds of the water capacity. A t the sticky point the volume of water held in the interstitial spaces of a colloid-free soil approximates to th e pore space of an ideal ” soil (26%). A. G. Po l l a r d.
Preparation of perm anent records of so il colour.
C. L. Wh it t l e s (J. Agric. Sci., 1931, 21, 189—190).—
A few drops of a suspension of the soil in water are filtered on a filter-paper disc in a Gooch crucible to form a thin and even film of soil. . After drying, the disc is removed and coated with celluloid varnish.
A. G. Po l l a r d. D eterm ination of hydrogen-ion concentration b y m ean s of the H aber-IClem ensiewicz g la ss cell, w ith special regard to soil in v estig atio n s. G. H a to s and G. G o ll (Magyar chem. F o l, 1930, 36, 33—39 ; Cliem. Zentr., 1930, ii, 121).—The Haber-Klemensiewicz cell can be used for determinations of hydrogen-ion concentrations. The ])& values for 15 soils determined by this means were practically in agreement w ith those obtained with the quinhydrone electrode, especially in dilute aqueous suspensions; in thick suspensions fluc
tuations amounting to 0-2—0-3 unit occurred.
L. S. Th e o b a l d. Influence of superphosphate on the reaction, base saturation, and buffer pow er of acid m in eral s o ils.
L. Sc h m it t (Superphosphat, 1931, 6, 219—227).— Continuous application of superphosphate did not appreciably affect the ]>n, buffer capacity, or exchange
able-base content of acid mineral soils, nor did it reduce the effectiveness of dressings of lime on these soils.
A. G. Po l l a r d. M easurem ent of the drillab ility of fertilisers.
A. L. Me h r in g (Ind. Eng. Chem. [Anal.], 1931, 3, 34—38).—The drillability of a fertiliser, i.e., the resultant of all factors influencing its rate of flow, is determined mainly by the coefficient of friction, apparent density, and particle size. A theoretical equation is given relating these factors to the tim e of flow of unit quantity through an orifice under the influence of gravity alone, and an empirical equation is given for the time of delivery of u n it quantity when pressure has to be applied to m aintain a steady flow. Appliances and methods for determ ination of the angle of repose, and hence of the coefficient of friction, and of the apparent density are described and an account is given of the calculation of the mean particle size from the percentages which pass sieves of various meshes. H. F. Gi l l b e.
E valuation of the available phosphoric acid content of fertiliser m a terials. C. C. Ho w e s and C. B. J a c o b s (Ind. Eng. Chem. [Anal.], 1931, 3, 70—72).—Results obtained by the standard method for insoluble phosphate in superphosphate containing ammonia fall by 50—70% if the usual 2 g. sample be replaced by 1 g. Alterations of the f n of the citrate solution between 4-5 and 8-8 cause great differences among the results, although in absence of ammonia no such effect is observed; similar discrepancies occur on variation of the quantity of citrate solution used and the period of digestion. I t appears th a t an entirely new method m ust be developed for ammoniated super
phosphate fertilisers. H . F. G i l l b e . [F ertiliser trials.] R. Tr n k a, L. St e t s k a l, and J. Ch r e u s t (Superphosphat, 1930, 6, 228—230).—
Ammonium sulphate was preferable to sodium nitrate as a source of nitrogen f or oats. Superphosphate increased the total crop and, in particular, the proportion of grain.
B etter proportional utilisation of soluble phosphates
B r itis h C h em ica l A b s t r a c t s —B .
3 1 2 C l. X V I.— Ag r i c u l t u r e.
was observed in podsols when superphosphate was applied in larger amounts than is customary.
A. G. P o l l a r d . Relation of nitrogen fertiliser to the firm n ess and com position of straw berries. J. S. S h o e m a k e r and E. W. G r e v e (Ohio Agric. Exp. Sta. Bull., 1930, No. 466, 20 pp.).—Spring applications of nitrogenous fertilisers to strawberry plants increased the nitrogen content and reduced the acidity of the fruit and increased the catalase activity of both fruit and foliage. The fruit was slightly softer, b u t its travelling quality was not appreciably affected. The total and reducing sugar contents of the fruit were increased by the fertiliser, and the percentage of all sugars increased with successive pickings. The yield of berries was not increased by spring applications of nitrogen, but marked increases resulted from autumn applications. A. G. P o l l a r d .
Potash in relation to cotton w ilt. M. N. W a l k e r (Florida Agric. Exp. Sta. Bull., 1930, No. 213,10 pp.).—
Infection of cotton by Fusarium vasinfectum is not reduced by applications of potash fertilisers.
A. G. P o l l a r d . Cabbage fertiliser exp erim en ts. A. B. F i t e (New Mex. Agric. Exp. Sta. Bull.. 1930, No. 180, 28 pp.).—
Highest yields were obtained by the use of cottonseed meal and with farmyard manure supplemented with minerals. Earliness of m aturity was closely associated with the total yields obtained. A. G. P o l l a r d .
A ction of inorganic sp rays on the germ ination and early grow th of cereals. H. L u n d e g a r d h , H.
B u r s tr o m , a n d H. E k s t r a n d (Kungl. Landtbruks- Akad. Hand. TidskT., 1930, 6 9 , 602—632; Chem.
Zentr., 1930, ii, 2176).—Stimulation was not observed with certainty. High concentrations retard germina
tion. Grain which germinates most rapidly is most sensitive to the toxic action. A. A. E ld r i d g e .
Chemical com position of som e N . Dakota pasture and h ay g rasses. T. H . H o p p e r and L. L. N e s b i t t (N. Dakota Agric. Exp. Sta. Bull., 1930, No. 236,39 pp.).
—A discussion of published data concerning variations in composition of numerous grasses with age and climatic conditions and of the effects of grazing.
A. G. P o l l a r d . M icrobiology of farm yard m anure decom posi
tion in soil. I. Changes in the m icroflora, and their relation to nitrification. II. Decom position of cellulose. H. L. J e n s e n (J. Agric. Sci., 1931, 21, 38—80, 81—100).—I. During the decomposition of manure in neutral or slightly acid soils there was a rapid multiplication of bacteria and to a less extent of actino- mycetes, and subsequently a sharp decline to a level approaching th a t of untreated soil. The initial increase in bacterial numbers was especially great where the manure contained fresh straw. The fungal population of soil was not affected by applications of manure unless fresh straw was included, when there was a considerable increase especially in acid soils. Nitrification of manure nitrogen occurred when bacterial numbers were declin
ing, bu t the process was never complete. The a-humus produced from manure contained 18—25% of the original nitrogen in an inert form which was not decom
posed in 6—12 months. The humus fraction of manure
consisted mainly of lignin combined with protein matter.
The rate and extent of the nitrification of manure was largely influenced by its C : N ratio. “ Edelmist.
having a lower C : N ratio than ordinary manure, was more rapidly nitrified, although, its nitrogenous con
stituents were not more easily decomposable. During decomposition in soil the C : N ratio of manure tends to approach 11—12 : 1 and no loss of nitrogen occurs. The relatively low fertilising value of the organic nitrogen of farmyard manure is ascribed to the utilisation of the available nitrogen by bacteria, which decline in numbers as the supply ceases. Mineralisation of this nitrogen then begins, but diminishes in rate and practically ceases before the whole of the nitrogen is attacked.
II. Decomposition of cellulose in soil is accompanied by a rapid increase in the numbers of organisms con
cerned, viz., those of the genus Vibris in soils of pu 6-5—7-0, Spirochaela ci/lophaga in soils of f n 5-7—6-2, and of fungi in more acid soils. Both bacteria and fungi decompose the lignocellulose of straw. The nitrogen requirements of cellulose-decomposing bacteria are not smaller than those of the fungi. The ratio cellulose decomposed : nitrogen assimilated was 25—54 : 1. Two fungi, bu t no bacteria, formed liumus-like compounds when grown on filter paper. A. G. P o l l a r d .
Potato scab and m anuring. B ic h i n g e r - (Super
phosphat, 1931, 7 , 8—16).—Effects of 9 years’ con
tinuous application of various fertilisers on the develop
ment of scab in potatoes are recorded. Superphosphate, ammonium sulphate, potassium magnesium sulphate, and probably potassium sulphate reduce scab infection.
Potassium chloride, if exhibiting any influence a t all, favours scab development. Chalk and basic slag, according to its free lime content, favour the spread of scab and reduce the beneficial effects of ammonium sulphate in this respect. Heaviest scab infections followed the use of sodium nitrate. Calcium cyanamide has a similar but less active effect. A. G. P o l l a r d .
M anuring of fish ponds. D. Br ü n in g (Enähr.
Pflanze, 1931, 2 7 , 49—54).—A discussion of observed results and of the conduct of experiments.
A. G. P o l l a r d . Influence of m anuring on drug yield s and esse n tial oil content of A n them is nobilis, L. 0 . D a f e b t and M. B r a n d l (Angew. B o t ., 1930, 1 2 , 212—215 ; Chem. Zentr., 1930, ii, 2157).—Cultural conditions are described. Young blossoms contain more oil th an old blossoms. The plant is very sensitive to phosphorus.
A. A . E l d r i d g e . Influence of tem perature and m oistu re on the nature and extent of decom position of plant residues b y m icro -o rga n ism s. S. A. W a k sm a n and F. C.
G e r r e t s e n (Ecology, 1931, 1 2 , 33—60).—Tho rate of decomposition of oat straw by soil micro-organisms increases with temperature. In 9 months a t 37 . 50—60% decomposition of lignin occurs, whereas a t 7°
the material remains practically unchanged. Addition of available nitrogen increases the rate of decomposition of hemicellulose and cellulose, bu t th a t of lignin is not appreciably affected. Lower tem peratures f a v o u r the synthesising activities of the organisms. A t higher temperatures decomposition processes predominate.
B ritis h C h em ica l A b s t r a c t s —B .
Cl. X V I.— Ag r i c u l t u r e. 31¡!
Tlie bearing of the above on the nature of humus pro
duced under different climatic conditions is discussed.
A. G. Po l l a r d. Cultivation of the sugar beet crop : three y e a r s’
investigations of the effects of sp acing. W. M.
Davies (J. Min. Agric., 1931, 3 7 , 973—985).—The optimum spacing of sugar beet in the West Midlands is probably 18 in. between the rows and 9 in. in the rows.
Spacing has no significant effect on the sugar content
of beet. E. Holm es.
Winter sp raying for the control of the apple capsid b u g. E. R. Pe t h e r b r id g e and G. L. He y (J.
Min. Agric., 1931, 37, 1078—1087).—From the sum
marised results of a number of trials it appears th a t a winter wash containing a ta r distillate and a mineral oil (approx. 7-5% of each) is best for the control of apple capsid bug, aphides, and red spider.
E. Holm es. E xterm ination of m a tg ra ss (N ardus stricta , L).
M. Malocii(Enâhr. Pflanze, 1931,2 7 ,54—56).—Autumn applications of kainite rapidly exterm inated matgrass from pastures. A. G. Po l l a r d.
Sulphur dustin g for the prevention of a bacterial disease of w heat, called B lack Chaff. F. J. Gr e a n e y
(Sci. Agric., 1931, 11, 274—280).—Repeated dusting with 15 lb. of sulphur per acre largely prevented the spread and development of th e disease.
A. G. Po l l a r d. T oxic effect of inorganic su bstan ces on sp ores of T illetia tr itic i. H. Bur str ô m (Kungl. Landtbruks- Akad. Hand. Tidskr., 1929, 68, 651—667; Chem.
Zentr., 1930, ii, 2176).—The toxicity falls according to the series (à) mercury, nickel, cobalt, copper, lead, palladium, zinc, cadmium, manganese, and (b) gold, chromium, ferric iron. A. A. El d r id g e.
E xam ination of tar and m in eral oil insecticid es.
H. Ma r t i n (J.S.C.I., 1931, 50, 91—9 4t).—A method for determining the oil content of mineral oil insecticides by ether extraction of the emulsion treated with caustic, soda is described. Factors which determine the suita
bility of the oil for spray purposes are discussed and methods are given for the determination of constants, e.g., specific gravity, viscosity, volatility, content of aromatic and unsaturated hydrocarbons, ease of oxida
tion, presence of sulphur compounds, deemed to be of value for this purpose. The oil used for the determ ina
tion of these constants is obtained, when possible, by breaking the emulsion b y the addition of saturated sodium chloride. The methods are applied to the determination of content of neutral ta r oils, ta r acids, and ta r bases of tar-distillate washes.
Calcium and h ydrogen-ion concentration and the interfacial tension of [insecticidal] pyrethrum extracts. R. P. Hobsox (J. Agric. Sci., 1931, 2 1 , 101—114).—The addition of pyrethrum extract to white spirit ” considerably lowered its interfacial tension against water. The tension decreased as the alkalinity of the aqueous phase increased. Addition of an emulsifying agent (agral W.B.) further lowered the interfacial tension, particularly against acid solu
tions, thereby decreasing the sensitiveness of the tension
values to the ])¡x of the aqueous phase. Calcium salts in the aqueous phase increase the interfacial tension, whilst alkali salts have the reverse effect. The tension values against solutions containing calcium and sodium salts can be correlated with the ionic ratio Ca" : OH'.
A. G. Po l l a r d. E valuation of p yrethrum flow ers (C h r y s a n th e m u m c in e ra rise fo liu m ). J. T. Ma r t in and F. Ta t- Te r s f ie l d (J. Agric. Sci., 1931, 21,115—135).—Existing methods for determining the toxic constituents of pyre- thrum are examined and modifications suggested. New methods for evaluating unadulterated samples and for the examination of individual flowers are described.
(Cf. Tattersfield and Hobson, B., 1929, 732.)
A. G. Polla rd . Volum etric determ ination of arsenic in in se cti
cid es etc. J. Pa s k u j (Magyar Chem. Fol., 1930, 36, 76—83,95—101; Chem. Zentr., 1930, ii, 1905).—The or
ganic material is destroyed with sulphuric acid and either hydrogen peroxide or nitric acid ; after addition of water, hydrochloric acid, potassium bromide, and ferrous sulphate, the arsenic trichloride is distilled off and titrated w ith potassium brómate by Gyory’s method (A., 1893, ii, 554). When hydrazine sulphate is substituted for ferrous sulphate, micro-procedure may be employed. A. A. El d r id g e.
L o n g -tim e m in eral feeding exp erim en t with dairy cattle. C. F. Hu f f m a n and O. E. Re e d (Mich.
Agric. Exp. Sta. Circ. Bull., 1930, No. 129, 11 pp.).—
Mineral supplement of calcium to an average ration of tim othy hay, silage, and grain for cows was unneces
sary. Supplements of bone meal improved the general health and milk production of the animals, though there was no effect on the duration of the lactation period or on susceptibility to infection (notably by B. abortus).
Prolonged feeding of rock phosphate inj ured the health and caused the formation of abnormal and badly worn teeth and enlargement and roughening of the jaw and leg bones. Supplements of limestone produced no adverse effects. A. G. Po l l a r d.
F eeding H e vea rubber-seed m eal for m ilk pro
F eeding H e vea rubber-seed m eal for m ilk pro