1880.] 



MICEOSCOPICAL JOUKNAL. 



55 



The arsenic that was found in the 

 stomach of the poisoned girl had a 

 yellowish tinge, probably caused by 

 the action of some sulphur com- 

 pound, which partly changed the 

 oxide into a sulphide. There were 

 no dust-like fragments, or very few, 

 the faces of the crystals showed the 

 peculiar parallel lines and triangular 

 markings or depressions, whicli are 

 produced by solvent action. 



The other gentlemen who touched 

 upon this subject in their testimony 

 did not differ from Professor Dana 

 to any noticeable extent. Professor 

 Brewer's evidence was almost iden- 

 tical. 



In closing these remarks about 

 arsenic, we must refer to some pho- 

 tographs of crystals of this substance, 

 kindly sent to us by Dr. T. D. 

 Williams, of Chicago. The photo- 

 graphs show certain characteristics 

 of the samples quite clearly, and 

 any person could readily distinguish 

 the different kinds. 



The testimony regarding blood- 

 corpuscles, is of a less satisfactory 

 character than that which relates to 

 the arsenic. 



Professor Wormley, of the Uni- 

 versity of Pennsylvania, Professor 

 White, of Yale, Dr. Treadwell of 

 Boston, Dr. Sanford and Dr. J. 

 J. Woodward were the principal 

 experts on the blood examina- 

 tions. 



A most embarrassing error, and 

 one which we would hardly deem 

 possible for a microscopist to fall 

 into, who was familiar with the 

 appearance of blood-corpuscles, was 

 made by Professor White. He 

 found an alga upon a stone and 

 mistook it for blood. Further ex- 

 amination enabled him to correct 

 the error; but the fact that the 

 mistake was made, shows the neces- 

 sity of extreme caution in such 

 examinations. One of the most 

 striking statements of all was made 



by Dr. Treadwell. In one instance 

 he testified, after measuring only 

 four corpuscles (having accidentally 

 lost the others) that ranged from 

 yttt" to TSTs" i^^ diameter, as 

 follows : " I am quite positive that 

 these were human blood-corpuscles, 

 and that they did not belong to 

 blood of the pig, sheep, goat, horse 

 or cat." In another place, referring 

 to some other examinations, he 

 stated that he had " obtained cer- 

 tain proof of human blood in one 

 instance only " (this was from stains 

 on a knife). Dr. Treadwell was 

 asked this question : " Now, Doc- 

 tor, if you have five specimens of 

 different bloods given you, will you 

 be able to say which are human ? " 

 He replied " Yes, if an honest and 

 competent man prepares the slides 

 for the microscope and with fresh 

 blood. Then I could give yon an 

 answer in a couple of hours." We 

 have not space to give the ad- 

 mirable testimony of Dr. Sanford 

 on this subject, which we regard as 

 perfectly reliable and correct. 



This review is based upon the 

 reports of the trial given by the 

 daily New York papers, which 

 seem to be quite reliable. 



Dr. Woodward speaks for him- 

 self in the following extracts from 

 a communication with whicli he 

 has favored us. 



Referring to the range and varia- 

 tion in the size of the corpuscles. Dr. 

 Woodward says : 



" What I actually testified as to 

 these points, was substantially as 

 follows : That the largest human 

 corpuscle I had ever measured in 

 any human individual, including 

 all ages, was -lOO-millionths (^Vo) 

 of an inch in diameter, the smallest 

 222-millionths (jiVo)- I said, how- 

 ever, that I did not for a moment 

 believe that these dimensions repre- 

 sented the extreme limits, for G. 

 Hayem {Recli. sur Vanat. normale 



