842 



THE POPULAR SCIENCE MONTHLY. 



said that for nearly forty years the sys- 

 tem of Linnaeus stood in the way of the 

 better system of Jussieu and De Can- 

 dolle ; that system in its turn has for a 

 third of a century been a clog and a hin- 

 drance to the adoption of the vivifying 

 idea that genetic ties are the true basis 

 for classification. The botanist in giv- 

 ing this new and illuminating order to 

 plants must be careful to discriminate 

 between primitively simple forms and 

 those simple by derivation. Parasites 

 are far from being the only plants that 

 have undergone simplification of struc- 

 ture; in willows and poplars, for exam- 

 ple, a single ovary has resulted from the 

 union of two or three ovaries. For 

 flowering plants Prof. Bessey presented 

 in detail a revised arrangement of the 

 Benthamian series. 



The Mutual Relations of Science and 

 Stock-breeding gave Prof. "W. H. Brew- 

 er, in his address to the Economic Sec- 

 tion, an opportunity of showing how an 

 art is broadened and bettered when it 

 flowers into a science. Until Darwin's 

 Origin of Species was published stock- 

 breeding followed the rule of thumb, 

 with results slow and uncertain ; to- 

 day, when heredity is understood as 

 due to influences largely calculable and 

 controllable, stock-breeding almost rises 

 to the assuredness of a plastic art. Prof. 

 Brewer spoke of a sheep-breeder of his 

 acquaintance who has all the ideality of 

 the true artist, who figures to himself 

 a perfect sheep with every good point 

 at its best, every defect eliminated ; in 

 striving to give substance to that form 

 as he imagines it, this man is as devot- 

 ed as any wielder of chisel or brush. 

 Breeding, said Prof. Brewer, can alone 

 decide whether acquired characteristics 

 are transmitted, and it may even throw 

 an important side light on vexed ques- 

 tions of education. 



Prof. E. L. Nichols, in his address to 

 the physicists on Phenomena of the 

 Time Infinitesimal, showed a bullet in 

 flight photographed in an interval so 

 brief that the missile seemed at rest. 



In another picture the bullet was shown 

 in the act of shattering a pane of glass, 

 with all the incidental perturbation of 

 the surrounding air. In giving rapid 

 motion to the sensitive plate Prof. Nich- 

 ols pointed out how its availability can 

 be vastly extended. In this field, he 

 maintained, there is abundant harvest 

 for the investigator, for when the time 

 interval is appreciable we do not get a 

 picture really instantaneous, but only 

 a composite photograph whose elements 

 we have to guess at. As to what hap- 

 pens in the first hundredths of a second 

 in the polarization of the voltaic cell, in 

 electrolysis, nothing is known, and here 

 possibilities of the highest interest await 

 the suitable application of the camera. 



In reviewing twenty-five years' prog- 

 ress in analytical chemistry Prof. Ed- 

 ward Hart brought out its remarkable 

 stimulus from the exigencies of industry, 

 and the no less remarkable fashion in 

 which the debt had been repaid. In 

 1868 the determination of phosphorus 

 in steel required two to three days; to- 

 day twelve minutes suffice. At the fur- 

 naces of South Bethlehem, Pa., a sample 

 of molten metal is passed upon by the 

 analyst while the iron is still on its way 

 to the converter ; the manufacture can 

 thus be intelligently directed with the 

 utmost promptness. This is but one of 

 the important Avays in which the chem- 

 ist has borne a part in cheapening iron 

 and steel. The work of analysis, in this 

 and other departments, has been greatly 

 quickened by developing those methods 

 which allow the chemist to determine 

 in a single specimen one constituent 

 rapidly and accurately. It is preferable 

 to determine phosphorus in one sample 

 and sulphur in another than to deter- 

 mine each separately in the same sam- 

 ple. In closing his review Prof. Hart 

 mentioned the honored chemists of 

 America who have notably contributed 

 to the world's advance in their science 

 during the past quarter of a century 

 men little known to a nation richer, 

 longer lived, and happier because of their 



