292 



NATURE 



[December 13, 1917 



Trouvelot and others, are to be utilised for a descrip- 

 tive account of the Messier objects in the proposed 

 series of articles. Following an interesting biography 

 of Messier, a useful list of the objects is given, with 

 the original positions and numbers, and positions for 

 1900, together with the N.G.C. designations. Mi and 

 Ma are described in detail in the first article, and each 

 is illustrated by a photograph, and by a drawing show- 

 ing the appearance in a telescope of 0-24 m. aperture. 

 It is interesting to note that the present publication 

 coincides with the centenary of the death of Messier, 

 who died at Paris in 1817, at the age of eighty-seven. 



SCIENCE IN INDIA A 



THE report of the Indian Association for the Culti- 

 vation of Science for the year 1915 contains, as 

 well as the usual presidential addresses, a miscellany 

 of scientific papers, ranging from ancient Hindu astro- 

 nomy and the metallurgy of the Rig Veda to modern 

 anthropological methods and problems of isomerism. 

 Physics and chemistry come in for more attention than 

 the biological sciences ; in the former category the 

 more important contributions are those of C. V. 

 Raman and Ashutosh Dey on discontinuous wave 

 motion, of S. Banerji on experiments with the ballistic 

 phonometer, and of J. C. Ghosh on a new method of 

 preparing colloids ; in the latter a careful and intelli- 

 gent analysis of the vegetation of the mouth of the 

 Hugh by N. B. Dutt must be mentioned. 



The address of the president, Raja Peary Mohun 

 iMukherjee, is a reminder that the association, although 

 it has always held the advancement of science by 

 research and experiment to be its final purpose, started 

 in life with a mission, which it still upholds, for im- 

 parting instruction in the general principles of science; 

 though brief, the address abounds in wise reflections 

 and sage advice adjusted particularly to the educated 

 youth of Bengal. 



Some of the special addresses allude to the recent 

 establishment of a University College of Science in 

 Calcutta, and to the opinions expressed in some quar- 

 ters that thereby the association, on its educational and 

 investigative side, may now be considered superfluous. 

 It is to be hoped that such short-sighted views may not 

 meet with any encouragement; for of all the miscon- 

 ceptions that have attended science since it was taken in 

 hand by bland official personages that about " over- 

 lapping" makes the most unfortunate departure from 

 inceptive truth. So far from being a stumbling-block, 

 overlapping in the domain of science brings manifold 

 strength and qumtessential purification, for the more 

 widely a scientific theory is tested and criticised the 

 less likelv is it to be a source of illusion. 



ALKALI SOILS AND SOIL SOLUTIONS. 



TN any attempt at agriculture in arid or semi-arid 

 ••• regions, considerable trouble is likely to arise from 

 accumulations of soluble salts at the surface of the 

 soil. The trouble is often intensified by irrigation, 

 and it may become so serious as to counteract the 

 advantages of a reclamation scheme that may be satis- 

 factory in other respects. In a recent issue of the 

 Journal of Agricultural Research, Dr. Breazeale esti- 

 mates that the losses from this cause have already 

 amounted to one hundred million dollars In the United 

 States alone, and the evil is by no means checked. The 

 soluble salts arise from two causes. Some come direct 

 from the weathering of soda feldspars, diorite, etc. ; 

 much, however, arises from the circumstance that the 

 area was once largely covered by marine lagoons or 



1 Report of the Indian Association for the Cultivation of Science for the 

 Year 1913. Pp. iii + iso. (Calcutta : Anglo-Sanskrit Press, 1917.) 



landlocked seas, the water of which evaporated, leaving 

 the salts behind. When the soils are first brought 

 under irrigation, the water applied to the higher levels 

 is usually excessive in amount, and drains through the 

 lower ground, carrying with it in solution considerable 

 amounts of the chloride, sulphate, carbonate, and 

 bicarbonate of sodium. Calcium carbonate is almost 

 invariably present in the soil, and both sodium 

 chloride and sodium sulphate react with this to produce 

 sodium carbonate, which is much more harmful to 

 vegetation than the other salts. The action is, how- 

 ever, reversible, and the addition of calcium sulphate 

 to the soil has long been a recognised method of re- 

 ducing the amount of sodium carbonate. The method, 

 however, has not always succeeded, and Dr. Breazeale 

 is able to furnish an explanation from his curves show- 

 ing the amount of carbonate formed from the various 

 sodium salts. If the carbonate is arising from the 

 interaction of sodium chloride or sodium nitrate with 

 calcium carbonate, then calcium sulphate is effective in 

 bringing about the reversal ; if it arises from sodium 

 sulphate, then calcium sulphate is without effect. 



The study of the soil solution is of great importance, 

 both in relation to soil formation and because it is the 

 me#ium for plant growth and the substratum for 

 microbial life. The difficulty is to obtain sufficiently 

 large amounts of the true soil solution. The drainage 

 water does not faithfully represent the soil solution, 

 soil extracts (using water as a solvent) only yield dilute 

 washings of the soils which cannot be concentrated to 

 reproduce the original solution, and the centrifuge only 

 separates moisture from a soil which contains more 

 than the optimum amount. A paraffin-oil displacement 

 method under pressure has been devised by van Such- 

 telen and Itano, which has been used by Mr. J. F. 

 Morgan. Some of the results obtained are described 

 in the June number of Soil Science. The method con- 

 sists of forcing paraffin oil, by means of a high-pressure 

 pump, through the soil tightly packed in a cylindrical 

 vessel, the pressure being raised so long as moisture 

 is expelled, until it reaches 500 lb. per square inch. In 

 the case of most soils ample solution for the necessary 

 analytical work is obtained — from sandy soils as much 

 as 74 per cent, of the moisture present — and a large 

 amount of solution is vielded without its coming in 

 contact with the oil. From the results of his experi- 

 ments the author concludes that the method furnishes 

 a fair representative of the solution as it exists in the 

 soil. Successive portions of the same extraction vary 

 only slightly in physical properties, but to a consider- 

 able extent in the various forms of nitrogen (am- 

 monia, nitrite, and nitrate). In the different soil solu- 

 tions phosphoric acid Is fairly constant, but calcium, 

 magnesium, and potassium vary, as do the forms of 

 ritrogen. The obtaining of a soil solution by the 

 method Is limited to the moisture content of the soil, 

 and depends upon the type of the latter, since all soils 

 are not entirely penetrated by the oil. Work Mr. 

 Morgan has In progress Indicates that the method fur- 

 nishes a valuable index of the microbial changes m 

 the soil. 



LOCAL NATURAL HISTORY SOCIETIES. 



npHE report of the Winchester College Naturah His- 

 ^ tory Societv for 1915-17, edited by its president, 

 the Rev. S. A. McDowall, shows that a considerable 

 amount of active work Is being done by the members. 

 Mr. McDowall himself is Interested in natural orchid- 

 hybrids, and he has succeeded In Infecting the older 

 members of the societ\- year by vear with his enthu- 

 siasm ; the present report contains valuable notes by 

 H. McKechnie and D. G. Lowndes, with five good 

 half-tone plates. The former also has an interesting 



NO. 25 1 I, VOL. 100] 



