SOIL PHYSICS,

CHEMISTRY

AND

MICROBIOLOGY

though at present their reports are transmitted by mail and therefore only serve to extend the isobars of the past month into high latitudes, it is hoped that in the not distant future wireless stations will be placed in the far North, as reports from such stations would afford most valuable data for the preparation of weather forecasts.

During 1911 balloons carrying the Dines Meteorograph were sent off with regularity, and of 21 sent up, 12 returned to the central office with good records. The heights reached varied from 11.2 to 23.2 kilometres. The isothermal layer was found at an average height of 12.6 km. ranging from 16 km. on November 8 to 9.5 km.on December 7. The lowest temperature recorded was-70°C at 15 km.on September 9. A kite station has been established at Agincourt, and observations of pressure, temperature, humidity and wind direction in the free air have since been obtained with fair regularity. The highest ascent yet reached is 2.408 m. (7900 feet) above sea level.

Newfoundland reccives forecasts and storm warnings from the Canadian Service, but maintains her own Meteorological stations and publishes her own weather bulletins. It is expected that before long both the Canadian and the Newfoundland reports will be cabled to England, where they will be of decided use to the British Meteorologieal Office.

There are at present 110 storm signal stations, 72 on tidal water aud 32 on the Great Lakes. The percentage of verification of forecasts for 1911 was 861 and of storm warnings 917. Mariners and fishermen pay close attention to storm warnings, while shippers of perishable goods consult the forecasts before shipping; moreover pilots of unseaworthy craft, such as dredges and barges, at all times of the year, and of all vessels during the late autunn, allow themselves to be guided from port to port by the meteorological official.

464 - Application of the Ammonium Carbonate Method for the Determination of Humus to Hawaiian Soils. RATHER, J B. Texas Agricultural Experiment Station, College Station, Texas. The Journal of Industrial and Engineering Chem

istry, Vol. 5, No. 3, pp. 222-223. Easton, Pa., March 1913.

The ammonium carbonate method for the removal of clay from humus has given uniformly good results on a number of the soil types of the United States, but on exceptional soils, like some of those of Hawaii, a slight modification of the method is necessary to remove the clay. The modification consists essentially in increasing the amount of ammonium carbonate to 2 gr. per 100 cc., and heating for one hour.

465 The Intensity of Nitrification in Arid Soils. - STEWART, R. Contribution from the Chemical Laboratoy, Utah Experiment Station, Logan, Utah, U. S. A. Centralblatt für Bakteriologie, etc. II. Abt. Vol. 36, Nos. 19-25, pp. 477-490. Jena, February 15, 1913.

The writer discusses the common conception that nitrification takes place with great intensity in arid soils. The discussion of former data,

particularly of Hilgard, of Headden and of the writer himself (1), leads to the following conclusions.

The conception that nitrification takes place with great intensity in arid climates rests primarily upon the observed fact that nitrates tend to accumulate in great quantities in certain arid soils. These nitrate accumulations always accur in connection with other water-soluble salts, such as sodium chloride and gypsum. No nitrate accumulations have been observed in arid soils free from other water-soluble salts. The alkali salts must therefore be intimately associated with the nitrates in one of two ways: Ist, they must exert a markedly favourable influence upon nitrification; or 2nd, the nitrates, like the other alkali salts, are of remote origin. From the data presented, it seems that the latter conception is the correct explanation.

The nature of the material out of which many of the soils of Utah and Colorado are formed seems to indicate that the nitrate accumulations found in these soils are undoubtedly of marine origin. The alkali occuring in many soils of Utah has been, in a large measure, deposited at the time of the formation of the shale; and, on the decomposition of this shale in the formation of the soil, the alkali has been incorporated with the latter. The passage of the water through the shale structure also washed out the soluble salts and carried them to the lower-lying land. The presence of the nitrates in the alkali soils of the arid belts, in addition to the possibility of injury arising therefrom, is of significance from other points of view. It is a well known fact that alkali soils a year or so before «going bad » produce a luxuriant growth of plants, which may be accounted for by the movement of the nitrates up to the feeding range of the plants, while a year or so later the salts become so concentrated as to cause the death of the plants.

Arid soils are markedly poor in organic nitrogen, and yet the crops produced are excellent. The soils are not «nitrogen hungry». Hilgard has attempted to account for this apparent anomaly by the assumption that since the small amount of humus in arid soils is relatively richer in nitrogen than the humus in humid soils, this fully compensates for the apparent deficiency in nitrogen. An appreciation of the tendency of the nitrates, formed during the past ages, to accumulate in arid regions is suggested as a better explanation of this fact, and as being not open to the mathematical objection that has been raised against Hilgard's assumption. The writer maintains that there is no reason to assume that the accumulation of nitrates in arid soil indicates a rapid bacterial action at the present time; but that these accumulations indicate a concentration of the nitrates already in the soil formed by slow bacterial action in the remote past. The application of the irrigation water has simply furnished a medium by which the nitrates may move, or be moved, from one place to another. This source of nitrogen affords a clear explanation

(1) See No. 775, B. April 1912; No. 897, B. June 1912.

(Ed.).

of the fact that in some cases the surface foot of cultivated arid dryfarm soils is richer in organic nitrogen than is that of the adjacent soils. The nitric nitrogen is obtained by the deep-rooted plants from the subsoil, converted into organic nitrogen by the plant, and then added to the surface soil by plowing under of the straw. The writer, however, fully realises that there is the possibility of ammonification, nitrification, and even nitrogen fixation taking place, to a certain extent, in some alkali soils at the present time; but from the data presented he assumes that the great accumulations of nitrates found in many alkali soils are of remote origin, being concentrated in their present position by the movement of the soil moisture.

Realizing fully that the term «alkali » must be so extended as to include not only the carbonates, chlorides and sulphates, but also the nitrates of the alkali metals, and recognizing clearly the source and method of nitrate accumulations in American arid soils, the writer believes one is in a position to work intelligently toward a solution of the problems presented by these unusual accumulations; and that the adoption of the methods of controlling the accumulations of alkali at the surface as suggested by Hilgard over twenty years ago, such as mulching, tillage and proper drainage, will convert the nitrate scourge into a blessing in disguise.

466

-

ROUSSELLE, V.: in Annales de la

Movement of Nitrates in the Soil (1). Science Agronomique, Year 30, No. 2, pp. 97-120. Paris, February 1913. A confirmation of Schloesing's results that no appreciable diffusion of nitrate takes place in the soil, but that layers of nitrate are merely displaced either downwards by percolation or upwards by the capillary

current.

467 - The Effect of Toluol and Carbon Disulphide upon the Micro-Flora and Fauna of the Soil. GAINEY, P. L. From the Twenty-Third Annual Report of

the Missouri Botanical Garden. Dec. 16, 1912.

The work presented was undertaken to determine whether the theory advanced by Russell and Hutchinson (2) was adequate to explain the phenomena subsequent to partial sterilisation when applied to local soils. The writer gleans from the literature the following evidences regarding such treatment.

(a) A temporary decrease in total number of bacteria present, with a subsequent large increase: Krüger and Heinze, Massen and Behn, Pfeiffer, Hiltner and Störmer, Russell and Hutchinson, Hutchinson aud Fred.

(b) An increase in oxidation: Fischer, Hesselink van Suchtelen, and Darbishire and Russell.

(Ed.).

(1) See No. 109, B. Feb. 1913.

(2) See No. 14, B. Jan. 1913; also RUSSELL, E. J.: Recent Investigations at Rotham

sted.

B. March 1913 pp. 336-341.

(Ed.).

(c) An increase in ammonification: Störmer, Scherp, Laidlow and Price, Lipman, and Russell and Hutchinson.

(d) A detrimental effect upon nitrification: Warington, Scherp, Laidlow and Price, Perrand, Pfeiffer, Wagner, and Russell and Hutchinson.

(e) A beneficial effect upon nitrification: Brailles, Wollny, Pagnoul, Störmer, Coleman, Lipman, Koch, and Fred.

(f) A detrimental effect upon nitrogen fixation: Störmer, Koch, Massen and Behn, and Koch and associates.

(g) A beneficial effect upon notragen fixation: Kranskii, Heinze, Lipman, and Fred.

(h) A detrimental effect upon denitrification: Wagner, Hiltner and Störmer, Störmer, Lipman and Fred.

(2) In regard to the effect upon nodule organisms: Wollny and Nobbe and Richter believed such effect beneficial, while Perotti, Koch and Fruwirth held the opposite view.

In addition to the above, Hiltner and Störmer, and Russell and Hutchinson have studied with some care the flora, as a whole, prior and subsequent to treatment; and they found that certain types were detrimentally and others indirectly beneficially affected. Russell and Hutchinson have also studied, more or less, the effect of such treatment upon the micro-fauna and, as a result, claim that all types of animal life, with perhaps one exception, are totally destroyed. Fred studied certain types of soil organisms in liquid cultures and found that the addition of certain strengths of various antiseptics stimulated development. The strength varied with different organisms and the stimulative effect diminished gradually from the maximum in both directions.

From the evidence brought forth in the experimental work the writer draws as justifiable the following conclusions:

I. That small quantities of carbon disulphide, toluol, and chloroform, such as have been used practically and experimentally (0.01-20 %, optimum 0.2%, when applied to the soils studied, exert a stimulative rather than a diminishing effect upon the total number of bacteria. present.

II. That an application of such quantities of carbon disulphide and toluol does not have an appreciable effect upon the number of types of protozoa present in such soils as have been studied.

III. That a very marked increase in yield may be noted following such an application when no evident change occurs in total number of bacteria present.

IV. That, in the light of the recent work of Koch, Egorov, Goodsey, Fred, and others, with results presented in this paper, the theory advanced by Russell and Hutchinson to account for the increased yield following the application of such chemicals, appears not tenable for general application.

A list of 40 references is appended.

PERMANENT IMPROVEMENTS, DRAINAGE AND

IRRIGATION

468 - Denitrobacterium thermophilum sp. nov.: a Contribution to the Life-History of Thermophile Bacteria. AMBROŽ, A. and CHARVÁT, J. Aus dem bakteriologisehen Institut der K. K. böhm. technischen Hochschule in Prag. - Centralblatt für Bakteriologie, etc., II. Abteilung, Vol. 37, Nos. 1-3, pp. 1-16 +2 figs. and I plate. Jena, March 8, 1913.

A description is given of a new denitrifying bacterium, Denitrobacterium thermophilum, which has been isolated from the soil, and of experiments concerning the nature of thermophilous denitrification, which process seems not to be confined to nitrates.

469 - Small Hill Reservoirs for Irrigation.

nura.

BRUTTINI, A. Laghetti artificiali o serbatoi costruiti in collina e collegati fra loro a gradinata, per l'irrigazione in piaL'Italia Agricola, Year 4, No. 7, pp. 169-171 +2 figs. Piacenza, 1913. This paper deals with a series of reservoirs (at present three) constructed by Prince di Lucedio, Carrega, on his estate Casino de' Boschi, near Sala Buganza, Parma, Italy.

The principle on which these constructions are designed may be adopted in all countries where arable lands in the plains are near hills or mountains.

Every hill or mountain is furrowed by small valleys in which spring or rain water flows, and as such valleys in some places widen and in others narrow, the plan was adopted of erecting successive barrages in the narrowest points of the valley, thus forming as many small artificial lakes, the arrangement of which, save for their greater dimensions, recalls the warping by steps as it is practised in Tuscany and in other countries for filling up ravines.

The base of every barrage is traversed by a a cast-iron pipe provided with a vertical sliding gate. Provision is also made for surface overflow. The valley acts as a canal between the successive reservoirs, the lowest of which supplies the water for irrigation, and is replenished by the upper ones. Thus the separate reservoirs are together equivalent to one large one, but have the advantage of costing much less to build and to keep up.

As for the technical and economical details of the work done, it may be stated that the first reservoir built contains 494 000, the second 1 589 000 and the third 742 000 cubic feet of water. The latter will be fed by other higher reservoirs, one of which is already being built and will contain 3 108 000 cub. ft. The cost price per 100 cubic feet of capacity in the various reservoirs is the following: Is 7d for the first reservoir, II 3/ d for the second, Is Id for the thid and Is for the fourth.

The dams are made of rammed earth laid in layers about 12 inches high, and watered, whilst being rammed, with lime water so as get a better cohesion between the particles of earth and greater impermeability to water. The base of the inner slope of the dam is twice the height of the latter, the base of the outer one being 1.5 times the height. The breadth at the top corresponds to the formula 3+(h-3). The dam is sunk into the ground to a depth of 6 feet.