Mar,, 1904.] 



KX0\\L1:DGK c^ SCIl'NTIFIC NEWS. 



43 



{Baihi/irgiis); and Mr. Bedd.ird discoursed on the arteries of 

 the base of the brain in certain nuunnials. Two papers by 

 Mr. G. .A. Boulen,t;er were also taken at the same nieetinf;, the 

 one dealing with throe new fishes from the Niger, and the 

 other with the type L-pecimen of the West African catfish 

 known as Clariiis /<i;'iiv/is. Ai the meeting of the same 

 Society, held on February 16, Mr. C. Crossland presented the 

 third instalment of a dissertation on the marine fauna of 

 Zanzibar and British ICast .Vfrica, dealing in this instance 

 with the polychietous annelids : and also a second paper 

 describing a collection of the same group of organisms from 

 the Mahay Peninsula. The third paper, by Sir C. l-.liot, dealt 

 with certain nudibranchiate molluscs from '/Cannhav and 

 British East Africa. 



A New GaLzelle from the White Nile. 



Considerable iiUerest attaches to the description by the 

 Hon. Walter Kothschild, in .W; iVii/tv /<i(ilof;iCiC, of a fine new 

 species of gazelle from the banks of the White Nile, which it is 

 proposed to call Giiztllii alhoiiotalti. 



BOTANICAL. 



HhKK LiNUEMi Til, of Bcrliii, has published in Cirtaitiora, 

 1903, Heft iS and 23, the results of his experiments on the 

 propagation of plants by means of their leaves. Horticul- 

 turists have long been accustomed to use this means of pro- 

 pagation in a few plants, notably in the Gluxinia and certain 

 Crassulaces, among which Bryuphylluin calycinuin is a well- 

 known example. It was, however, probably not suspected 

 that the leaves of so many plants could be made to produce 

 roots. In his first communication Herr Lindemuth gives the 

 names of twenty-eight species, of nearl)' as many different 

 genera, in which his experiments have been successful. These 

 include such plants as the Foxglove {Digitalis purpurea), the 

 Musk [Miinulus moschatus), the Tomato, and the Vine. The 

 leaves of thirteen species, including the Potato, Monkshood 

 (Aconilum Xapcllus), and the common bedding Geranium 

 {Pelargonium zoitaU) refused to root at all. Usually the roots 

 were produced quickly — in the Vine in sixteen days, in 

 Veronica in seven days, and in the African Marigold in eight 

 days — but the amount of time required, and, indeed, success 

 at all, was shown to depend very much on the season when 

 the experiments were made. Thus, in the Vine, roots were 

 developed in sixteen days in .August ; but complete failure 

 resulted in September, when the leaves perished. In his 

 second communication, the author records success with thirty- 

 four additional species, including three of those with which he 

 had met with failure before. The results so far obtained shovv 

 that few of the leaves thus experimented on will form buds, 

 only five having done so. In the case of a species of Citrus, 

 the leaves rooted and persisted for months and even years 

 without any further development. — S. A. S. 



Recent Research in Agricuhure- 



Mr. Hall, the Director of the Rothamsted i:xperimcntal 

 Farm, lecturing at the Royal Institution on " Recent Research 

 in Agriculture," dealt with the growth of wheat, still an impor- 

 tant crop in Great Britain, despite the fact that the area under 

 wheat has shrunk from more than four million acres in i860 

 to less than i,.Soo,ooo at the present time, and that we only 

 now produced about seven million quarters, and had to im- 

 port more than 25 million (luarters. The English yield 

 averaged, however, more than ji bushels per acre, consider- 

 ably greater than that of any other country, and double or 

 treble that of the chief countries who send us wheat. The 

 lecturer then showed, by examples drawn from the Rotham- 

 sted experiments, that the production of wheat could be 

 greatly raised by the use of manures, but that this process 

 soon ceased to be profitable—"' high farming is no cure for low 

 prices." A further difficulty to be faced by the English wheat 

 grower is the comparatively low price of this product, the best 

 Manitoba or Russian or Argentine wheat realising 20 to 25 per 



cent, more than the best English wheat. This dillereiicc of 

 price is due to the greater '• strength " of the flour made from 

 such foreign wheats, meaning by " strength " the capacity to 

 make more and larger loaves for equal weights of lloiir used. 

 The lecturer illustrated tlie point by exhibiting loaves baked 

 from eijual weights of luiglish and .American llour, the 

 .\niorican one being decidedly larger ;iiid more attractive in 

 appearance. For some time the lecturer had been concerned 

 with ;in en(|uiry initiated by the National .Association ol 

 Millers, and helped by the Board of .\griciilture, as to the con- 

 ditions which brought about " strength " in flour, and how 

 ICnglish wheat could be impro\ed in this respect. Climate 

 being one of the chief factors, the lecturer contrasted the 

 ICnglish climate with thai of the Hungarian Plain and of the 

 North West. The development of wheat, the r.ite of forma- 

 tion of the grain, and the migration of the nitrogenous con- 

 stituents into the grain was then studied at Rothamsted, and 

 compared with similar results obtained in Hungary ; all tend- 

 ing to show that strength is associated with a short period of 

 ripening. Strength is dependent on the nitrogenous content ol 

 the wheat, but the attempts to correlate it more exactly with 

 total nitrogen, with gluten, or with the ratio between gli.adin 

 .uid glutenin, as certain French and .American chemists have 

 done, fail to show consistent results. Climate is not, however, 

 everything in causing strength, for even among b^nglish 

 wheats some are much strongc'r tlian others. Certain 

 foreign varieties also when introduced into this country retain 

 to a very considerable degree their strength, at any rate for 

 three or four years. However, they generally give crops con- 

 siderably below the English stand.ird, though for late spring 

 sowing some of the best, like No. i Hard Manitoba, .are prob- 

 ably ecjual to .any lingllsh varieties. As "strength" is a 

 (|uality inherent in the variety, it is capable of improvement 

 by cross-breeding .and selection, and a considerable amount of 

 % ery promising work has idready been done in this direction, 

 the disideralum being increased strength with the cropping 

 powers of the best I-Inglish varieties. The lecturer exhibited 

 various loaves made from English and foreign varieties of 

 wheat grown in this country to illustrate the foregoing points. 



PHYSICAL. 



Photography in Natura.! Colours. 



Thl principal novelty of a process lor obtaining photographs 

 with natural colours, just brought out in Berlin, is the fact 

 that any ordinary negative may be made to give chromatic 

 prints with the original colours. Suppose a view of a lands- 

 cape to be taken with an ordinary plate; the sky being blue, 

 will throw on the plate the most efficient light, so as to pro- 

 duce on the negative the thickest dark layers. The leaves of 

 the trees, on the other hand, will produce less intense effects, 

 and still less will be the action of the red portions. Now the 

 in\ entor, Oberleutnant von Slawik, .an .Austrian, has designed 

 a special kind of pigment paper, bearing a nuinber of super- 

 posed dye-stull layers ; underneath there is a red layer, in the 

 middle a green, and above a blue layer. Now the most 

 strongly C(jvercd portions of the negative -representing the 

 sky — will evidently be the least translucent, the light actually 

 penetrating being able to act only on the upper blue layer, 

 rendering insoluble only the chromium jelly constituting this 

 layer. The thinnest portion of the negative, corresponding 

 for instance to a red wall, will in printing transmit the 

 greatest amount of light ; all three pigment layers thus being 

 struck l)y the light will become insoluble down to the loA-est 

 red layer. The green leaves will, as above shown, give rise 

 to a covering of the plate of medium intensity, a medium 

 amount of light penetrating the paper at the corresponding 

 portions of the plate, this amount of light being just sufficient 

 to render insoluble the two upper blue and green strata, 

 whereas the lowest layer will remain unaltered. 



.After printing, the paper, as usual, is pressed on another 

 sheet of paper, when the coloured layers are transferred from 

 one sheet to the other, the printing being afterwards "deve- 

 loped " with warm water, in the way usual in pigment printing 



