Nov. 12, 1885] 



NATURE 



47 



for some crops, especially potatoes, in cases of a deficient supply 

 of potash in the soil, they have sometimes proved invaluable. 

 In general, however, cost and efficiency are closely associated, 

 and as plants and animals are almost alike in their chemical 

 composition the same rule as to the value of their conUituents 

 holds good. Vou may |)urchase starch and the carbo-hydrates 

 at a much lower rate than the nitrogenous substances in food. 

 Turnips, bread fruit, and bananas, consisting chiefly of carbo- 

 hydrates, are sold by their respective growers at a very different 

 and mucli lower price than milk or peas, which are rich in albu- 

 minous elements. In every form nitrogen is always compara- 

 tively costlj'. The albumen in eggs, the fibrine in cereals, the 

 casein in milk, and the legumin in peas and beans, all owe their 

 importance and cost to this particular element, which is the 

 source of force and vigour, of the labour of the hardest-worked 

 cattle and men, of lean meat and muscle. 



Considering the limited supply of nitrogen and the cost of 

 obtaining it, it is not su.prising that it should often be present 

 in cultivated soils in quantities insufficient for a full cop, and 

 that the land, when dressed with salts of nitrogen, should answer 

 to their touch as a horse does to the spur. In the Rothamsted ex- 

 periments the unmanured field yielded for years about fourteen 

 bushels, or half a crop, till a dressing of nitrogen was given to 

 it, when immediately the crop was doubled, nitrogen having 

 been, as it often is in clay soils, the one thing needful to a full 

 crop. Sir John Lawes has been sometimes asked by American 

 farmers how to restore the exhausted fertility of their fields, so 

 that the land, yielding fourteen bushels per acre, which is about 

 the average of corn-exporting countries, might be induced to 

 return twice as much. It is fortunate for English farmers that 

 Sir John can only send advice into the far West ; he cannot 

 send nitrogen. 



Some years ago the agricultural community was flattered by 

 the immediate prospect of a never failing supply of nitrogen. 

 The marvels of chemistry and analysis had recently been un- 

 folded by the writings of .Sir H. Davy and Baron Liebig, and 

 the efficacy of guano had accustomed farmers to the new method 

 of supplying nitrogen to the land in concentrated forms and from 

 sources outside the farmyard. Then came the promise of ob- 

 taining nitrogen from the atmosphere. The agricultural classes 

 are rarely much moved by anything but bad weather and falling 

 prices, and the chemists had explained to them that the nitrogen 

 of the atmosphere, existing as it does in a free state mixed with 

 oxygen, was not available for agricultural purposes. If it could 

 be induced, they were told, to enter into combination with 

 hydrogen the result would be ammonia, an invaluable manure. 

 This was understood by farmers, and a great sensation was 

 occasioned among them when Mr. Nasmyth, the inventor of the 

 steam hammer, proposed to control the supply of the most costly 

 of plant constituents by knocking it out of the atmosphere. It 

 is easy to see that if Mr. Nasmyth had succeeded in knocking 

 nitrogen and hydrogen into combination at a moderate cost, a 

 revolution in the price of manures and of food must have speedily 

 occurred. 



But as the plan failed and as plants still " live and move and 

 have their being" in the midst of an element which they cannot 

 feed on, it was certainly surjjrising to learn lately that nitrogenous 

 manures had ceased to produce their accustomed effect. The 

 phenomenon occurred at the Duke of Bedford's experimental 

 farm at Wobuvn, where, according to official statements, the 

 yield of wheat manured by the dung of animals fed on maize 

 proved as abundant as the crop which followed from manure 

 produced by the feeding of cotton cake, which enriches the 

 excreta with far more nitrogen than that produced by feeding 

 maize. 



The Woburn experiments were instituted by the Royal Agri- 

 cultural Society and w^ere placed under the manageinent of its 

 chemist, the late Dr. Voelcker, for the purpose of testing the 

 value of manure obtained by the consumption of different kinds 

 of food and to compare the eftects of such manures with those of 

 artificial manures. It is evident that in such 3 comparison the 

 land to which the various fertilisers were applied should have 

 been of similar quality. But there are other disturbing causes 

 which may vitiate experiments of this kind, and these were not 

 at first generally recognised. The mistake occurred in some 

 rotation experiments in which the manure derived from cotton 

 cake containing about 40 per cent, of nitrogenous constituents 

 was compared in its results with that obtained from maize, a 

 cereal containing only 10 per cent, of albuminoids. The results 

 of these experiments were known to the agricultural community 



before the report of Dr. John Voelcker, who has succeeded his 

 late father as chemist to the Royal Agricultural Society, had 

 been made, and much surprise was expressed that at the close of 

 the second rotation the cotton cake had not shown any decided 

 superiority over the maize. It has been recently explained in 

 an official report on the "Objects, Plan, and Results of the 

 Woburn Experiments," that this was "probably due to the large 

 amount of unexhausted manure in the land." Before commenc- 

 ing experiments, therefore, on the comparative value of manures 

 the land should be exhausted by repeated scourging crops, as at 

 Rothamsted, where in some cases the deep-rooting Bokara 

 clover has been grown for the special purpose of [reducing the 

 fertility of the sod to nil. 



It haslongsince been established that nitrogen is neither absorbed 

 by plants from the atmosphere nor conveyed into the soil to any 

 appreciable extent in any way except by the direct application of 

 manure : still there are some crops which collect nitrogen and 

 leave the surface-soil richer than before. Red clover is usually 

 grown as a preparation for wheat, and although clover hay must 

 necessarily withdraw a great deal of plant-food from the soil, it 

 does not prove exhaustive in practice because the deep and fleshy 

 roots of the plant collect nitrogen from the subsoil and, in their 

 decay, supply it to the growing wheat-crop. Under such 

 circumstances a strong nitrogenous manure may not be required, 

 and may perhaps prove less desirable than a weak manure con- 

 taining less nitrogen. Enough has been said to show that the 

 field experiments which are now becoming popular, and which 

 are being instituted at many "stations" throughout the country, 

 will require great care and the supervision of managers who 

 possess a competent knowledge both of "practice and science." 



H. E. 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE 



London. — In accordance with resdutions passed at the extra- 

 ordinary meeting of the Convocation of the University of London 

 held on July 28 last, an adjourned extraordinary meeting of the 

 House was held on Tuesday week in the University Building, 

 Burlington Gardens, which was very numerously attended. The 

 Chairman of Convocation (Mr. F. J. Wood, LL.D.) presided, 

 and in his opening address explained his ruling that under the 

 said resolutions the business pending before the former meeting 

 might now be proceeded with, and invited the House to resume 

 the debate accordingly. At the time of the adjournment the 

 House had a motion before it, made by Lord Justice Fry, for the 

 reception and adoption of the report of the special committee 

 appointed to cmsider the project of the " Association for Pro- 

 moting a Teaching University for London." To this motion an 

 amendment had been moved by Mr. J. W. Bone, seconded by 

 Mr. Philip Magnus, omitting all the words in the original motion 

 after the word "received." At Tuesday's meeting leave was 

 given to Lord Justice Fry to accept the amendment, which thus 

 became a substantive motion, to which his Lordship, however, 

 immediately proposed to add "And that the House now con- 

 sider what amendments, if any, ought to be made in the said 

 scheme, and that such amendments, if any, be by way of instruc- 

 tion to a committee of revision." For Lord Justice hry's motion 

 76 only voted against 122 who negatived it. Ultimately after a 

 three hours' sitting the debate was adjourned to Tuesday, 

 December 8. 



Alderman Sir R. N. Fowler, Bart., M. P., has consented 

 to present the City and Guilds of London Institute's Scholar- 

 ships, Prizes, and Certificates at a meeting to be held on 

 Wednesday evening, December 9, at the Salters' Hall, St. 

 Swithin's Lane, E.C. The Right Hon. the Lord Mayor will 

 preside. 



SCIENTIFIC SERIALS 



Miltheilungen der Naturforschindcn GeuHschaft hi Burn, Nos. 

 1064. to 1091, 1883-4 (three parts). — Contributions to the 

 doctrine of metal-poisoning, by J. Marti. — Terrestrial and 

 fresh-water moUusca collected in the neighbourhood of Berne 

 and Onterlacken, by G. Regelsperger. — An automatically- 

 acting thermograph, by G. Hasler. — Influence of sexual excita- 

 tion on the composition of cow's milk, by F. Schaffer. — Furthei 

 paper on the animal world in the pile-dwellings of the Lake of 

 Bienne, by Th. Studer. — On a parasite in the intestine of the 

 horse, by M. Flesch. — On the nature of odorous matters and 



