CHEMISTRY. 



145 



and ammonia; then treats with solution of 

 potash, suJphureted hydrogen, and hydrochlo- 

 ric acid. . After boiling and cooling, uric acid, 

 mixed more or less with cyanuric acid, and a 

 little coloring-matter, are deposited. The uric 

 acid is separated from the cyanuric acid by 

 further treatment with the ammoniacal solu- 

 tion of silver and magnesia. Although the 

 yield is small, the crystals of uric acid are well 

 marked, answer to all the required microscopic 

 tests, and respond perfectly to the murexide test. 



Ladenburg has prepared piperidine, with 

 nearly the quantitative yield, by treating pyri- 

 dine with sodium in alcoholic solution, and has 

 also obtained some interesting homologues of 

 that base. 



The general impression seems to prevail that 

 the synthetical production of the vegetable al- 

 kaloids will soon be accomplished. "While it is 

 very probable that every compound produced 

 in the vegetable organism may ultimately be 

 obtained artificially, a knowledge of the con- 

 stitution of these compounds must first be ac- 

 quired. The most important result of recent 

 investigations in this field is the demonstration 

 that many of the alkaloids are definitely, others 

 very probably, to be considered derivatives of 

 quinoline and pyridine. Thus, in the case of 

 quinic acid, which differs from quinoline by 

 the substitution of two radicals for two hy- 

 drogen-atoms, as the structural formula of 

 quinoline admits of 42 possible acids of the 

 composition of quinic acid, it has to be deter- 

 mined which of the 42 isomers quinic acid 

 really is, and this has been done with a certain, 

 but not full, measure of success. Morphine is 

 probably a derivative of pyridine, and stands, 

 at the same time, in close structural relation 

 to the hydrocarbon phenanthrene; but there 

 is still a great gap between the knowledge 

 of these isolated facts and the artificial pro- 

 duction of this alkaloid. Atropine, the ac- 

 tive principle of belladonna, has been recon- 

 structed synthetically from its decomposition 

 products, tropic acid and tropine. Tropic acid, 

 also, has been artificially prepared, but we are 

 still ignorant of the constitution of tropine. 

 Hence, we have as yet no method of producing 

 atropine independently of the plant from which 

 it is now obtained. But granting that the 

 structural composition of the alkaloids was 

 clearly established, their production on a tech- 

 nical scale would still probably be impractica- 

 ble, for it is likely that the materials necessary 

 for their artificial manufacture would be too 

 costly and the processes too complex for avail- 

 able use. Mr. Oresswell Hewett has, how- 

 ever, announced that he has discovered a pro- 

 cess for the synthetical manufacture of quinine 

 from an article that exists in abundance every- 

 where, whereby the price of that drug may be 

 greatly reduced. 



W. H. Green obtains saligenin synthetically 



by heating determined quantities of methylin 



chloride, phenol, and sodium hydrate dissolved 



in water, for six hours. The contents of the 



VOL. xxvi. 10 A 



matrass are neutralized with hydrochloric acid, 

 and the saligenin is extracted with ether. 



Atomic Weights. Brauner has estimated the 

 atomic weight of cerium from the eerie oxide 

 left after ignition of anhydrous cerous sul- 

 phate. Twenty-three determinations gave a 

 maximum atomic weight of 140,433, a mini- 

 mum of 140,033, and a mean value of 140,- 

 210 ; thus harmonizing the periodic values of 

 the group. H. Robinson has criticized the 

 work of Wolf, on which the atomic weight 

 (138) given for cerium in Clark's " Constants 

 of Nature " is based, maintaining that Wolf's 

 method of preparation would give lanthanum 

 and not eerie oxide. 



Prof. Cl. Winkler has provisionally fixed the 

 atomic weight of germanium at 72-75, and 

 has assigned it a rank between silicon and tin, 

 as the " eka-silicon " of Mendelejeff's classifi- 

 cation. M. Lecoq de Boisbaudran had calcu- 

 lated the atomic weight of the hypothetical 

 body between silicon and tin to be 72-28, tak- 

 ing Si = 28 and Sn = 118. A spectroscopic 

 examination of a specimen of the metal re- 

 ceived from Prof. Winkler gave 72 '32 ; repeat- 

 ed with a modification for the avoidance of a 

 probable uncertainty, it gave 72-27. 



John Waddell, conceiving that previous de- 

 terminations of the atomic weight of tungsten 

 might have been vitiated by the presence of 

 molybdenum and silica, undertook a new de- 

 termination with samples from which those 

 impurities had been carefully removed, em- 

 ploying, with his processes, a new method of 

 purification, by fractional precipitation. The 

 result of his experiments was the deduction of 

 184'5 as the atomic weight of tungsten, that of 

 oxygen being taken as 16. This is confirma- 

 tory of previous investigations of the subject, 

 and of the accuracy of the commonly accepted 

 atomic weight of the element in question. 



Chemistry of Plants. V. Meyer and E. Schulze 

 have made researches on the action of hy- 

 droxylamiue salts upon plants, with the expec- 

 tation of finding that this plays an important 

 part in the synthetical activity of vegetation. 

 They instituted parallel experiments on the 

 culture of maize, to which nitrogen was sup- 

 plied in the form of ammonium sulphate, hy- 

 droxylamine sulphate, and hydrochlorate and 

 potassium nitrate. The result was to show 

 that the hydroxylamine salts act as direct 

 poisons to plant-life, as Bertoni has shown they 

 do toward animal life. Having established this 

 fact, the authors inferred the probable action 

 of the salts as antiseptics, and experiment 

 showed that they partake this property in a 

 remarkable degree. 



M. E. Maumene" has found manganese in 

 wines and in a considerable number of vege- 

 table and animal products in which it had 

 hardly been supposed to be present ; and now 

 announces, as the result of his latest investiga- 

 tions, that he has detected it in a great many 

 plants. Wheat contains not less than from 

 to iroV<5 of metallic manganese, and rye, 



