120 



THE AMERICAN MONTHLY. 



[June. 



not this an oversight? I have been un- 

 able to procure it in drug-stores. Messrs. 

 Eimer & Amend, after much trouble, sent 

 me a small sample, perhaps half an ounce, 

 which had been taken from a private col- 

 lection of drugs. Druggists down South 

 even rarely have it. That used by Euro- 

 pean mounters usually comes from Cen- 

 tral or South America, and can only be 

 obtained from one or two firms. The sty- 

 rax or storax of the shops is the gum of 

 L. oricntalc (more or less pure). It is 

 much darker, more sticky, and has a far 

 stronger odor, at times nearly sickening. 

 I much prefer the American gum, and 

 have entirely discarded the ordinary sty- 

 rax of the drug stores. 1 think upon ex- 

 amination you will find that I am correct. 

 I am glad to see that you are publishing 

 a translation of the article on staining from 

 the Zeitschrift f. Wisscn s. Mikroskopie ; 

 the original is certainly excellent. Your 

 readers generally should be pleased. 



A. B. AUBERT. 



NOTICES OF BOOKS. 



Micro-Chemistry of Poisons, including 

 their Physiological, Pathological, and 

 Legal Relations ; with an Appendix on 

 the Detection and Microscopic Dis- 

 crimination of Blood: Adapted to the 

 use of the Medical Jurist, Physician, 

 and General Chemist. By Theodore 

 G. Wormley, M. D., Ph. D., LL.D., 

 Professor of Chemistry and Toxicology 

 in the Medical Department of the Uni- 

 versity of Pennsylvania. With ninety- 

 six illustrations upon steel. Second 

 edition. Philadelphia: J. B. Lippincott 

 Company. 1885. (Large 8vo, pp. 741 

 and 17 plates. Price: Cloth, $7.50; 

 sheep, $8.50.) 



This work is not merely a treatise on 

 the detection of poisons with the micro- 

 scope, but a complete manual of toxicol- 

 ogy for the physician and chemist. The 

 microscopical characters of the crystals 

 of such compounds as are in any wise 

 characteristic are described, and beauti- 

 fully dehneated by Mrs. Wormley, who 

 has made all the engravings on steel. 

 The quantities of poisons that can be rec- 

 ognized are in some cases truly micro- 

 scopic. For instance, i-ioooo of a grain 

 of arsenic, mercury, strychnine, or hydro- 

 cyanic acid can be recognized with abso- 

 lute certainty — indeed, i-iooooo of a grain 

 of hydrocyanic acid will give a character- 

 istic crystallin'e compound. 



Perhaps we can do no better than to 

 quote a few paragraphs from the book to 

 show the concise and clear style of the 

 writer, who, it need scarcely be said, has 

 no superior in toxicology. For this pur- 

 pose we will choose the reaction of mer- 

 curic chloride with nicotine, as this is a 

 test which can readily be repeated by the 

 reader. The reactions are carried out in 

 watch-glasses. 



' ^- T5U grain of nicotine in one grain of 

 water yields a copious white precipitate, 

 which in a little time becomes yellow, and 

 yields a mass of large groups of crystals. 

 These crystals are especially beautiful 

 under polarized light. 



'2. ^^ grain: yields a rather copious, 

 dirty-white precipitate, which soon depo- 

 sits colorless crystals. 



'3. x^jiji grain: in a few seconds the 

 mixture becomes turbid, and soon there 

 is a quite good, white, flocculent precipi- 

 tate, which afterwards yields crystals hav- 

 ing the same forms as illustrated above. 

 If, upon the addition of the reagent, the 

 mixture be stirred with a glass rod, it im- 

 mediately yields streaks on the bottom 

 of the watch-glass over the path of the 

 rod.' 



The Appendix treats of blood, its com- 

 position, detection, and discrimination. 

 Some of the measurements of the cor- 

 puscles are quoted on another page. The 

 conclusion as regards the possibility of 

 microscopical discrimination is given in 

 these words: — 'The microscope may en- 

 able us to determine with great certainty 

 that a blood is not that of a certain ani- 

 mal and is consistent with the blood of 

 man ; but in no instance d i«s it, in itself, 

 enable us to say that the blood is really 

 human, or indicate from what particular 

 species of animal it was derived.' 



The book is invaluable to all who 

 are interested in the applications of the 

 microscope in chemistry and toxicol- 



ogy- 



Exchanges. 



[Exchanges are inserted in this column without 

 charge. They will be strictly limited to mounted ob- 

 jects, and material for mounting.] 



Seeds of Orthocarpus purpurescens , in exchange 

 for other objects, mounted or unmounted. 



EDWARD GRAY, M D., 

 Benicia, California. 



Diatoms ceous earth from Denver, Colorado, in ex- 

 I change for mounting material. 



H. B. CHAMBERLIN. 

 280 Fifteenth St., Denver, Colorado. 



