1674 Journal of Applied Microscopy 



[ NEWS AND NOTES. ] 



American Microscopical Society. — The twenty-second volume of the 

 Transactions of the American Microscopical Society, which has recently been 

 issued, contains the papers and proceedings of the twenty -third annual meeting 

 of the society, held in New York City on June 28th, 'Idth, and 30th, 1900. 

 The volume consists of two hundred twenty-eight pages and thirty platts. Of 

 the thirteen papers, nine are upon subjects which are more or less limnological 

 in character. 



Following the usual custom, the volume opens with the president's address, 

 the subject on this occasion being " The Detection and Recognition of Blood." 

 The author. Dr. A. M. Bleile of Columbus, Ohio, draws attention to the extreme 

 importance, especially in certain legal proceedings, of being able to determine 

 the presence of blood as distinguished from other substances of similar color, 

 and to demonstrate whether it is from a human being or from one of the lower 

 animals. As there are only two characteristics, viz., red corpuscles and haemaglo- 

 bin, by means of which blood can be distinguished from all other substances, the 

 tests are necessarily limited to proving the presence of one or the other of these 

 elements. The red corpuscles are so easily distorted and shrunken by exposure 

 to the air and it is so difficult to restore them to their normal size and shape, 

 although several methods have been claimed by their inventors to be satisfactory 

 for this purpose, that no reliable microscopist would attempt at the presert time 

 to identify corpuscles of human blood by their microscopic characters alone, 

 especially since it is known that in their measurements and contour the rtd cor- 

 puscles of several of the domestic mammals are so much like those of man that 

 the various kinds cannot be positively separated by these features alone. If the 

 remains of red corpuscles are found the nature of the fluid is at once shown, but 

 in old stains it is very difficult to restore their bodily shape even though the 

 color of the stains may be characteristic. Recourse is then made to the coloring 

 matter, haemoglobin, itself. The most reliable chemical test for this substance 

 is Teichmann's, directions for which will be found in almost all text-books on 

 histology, but one of greater delicacy and more certainty requires the use of the 

 spectroscope. The reliability of the spectroscopic test is not, in the author's 

 experience, impaired by the age of the stain, the influence of heat, nor the effect 

 of strong chemicals and preservative fluids. The test is made as follows : After 

 an attempt to find red corpuscles, and with or against success in this direction, 

 without wasting further time or material which may be at disposal in small quan- 

 tities only in a search after the less delicate haemoglobin or the hemin crystals, so 

 liable to fail, the substance is to be at once treated with KHO solution (5 per 

 cent.), using heat if necessary, to effect solution, then adding pyridin (J^ its 

 volume), and then (NH4)2S, and observing the spectrum. Where a small stain 

 on a thin fabric is the object of study, it can be placed on a thin cover-glass, 

 moistened with a drop of KHO solution and pyridin. After some minutes a 



