Tests with Predpitins 385 



fowl, goose, ox and pig blood did not. He gathered the impression that 

 the older the blood, the less intense is the clouding, for he never obtained 

 a regular precipitum with old dried blood. 



I have noted elsewhere that there are drawbacks to using soda 

 solution, because of the pseudo-reactions it may give (see pp. 64 and 83), 

 also to the necessity of observing a " time limit," facts which detract 

 from the value of Ziemke's observations. He did not state that controls 

 were used in all his tests, nor that the control bloods were also diluted 

 with soda solution. 



Uhlenhuth (25. vn. '01) next reported experiments upon blood- 

 stained articles. He obtained positive reactions with human blood- 

 stains on a stick (1900), blood-stained sand (1896), a stain on cotton 

 (1897), a stain on a coat and pair of trousers (1901), and on a hatchet 

 (1900), upon adding anti-human serum to saline solutions of these bloods. 

 With anti-pig serum he obtained positive reactions with pig blood-stains 

 on linen (anti-human, anti-sheep, anti-horse sera gave no reaction), also 

 with blood dried since 1897. Anti-pig serum gave a reaction with 

 a mixture of sheep and pig blood (dried 1889), also with solutions of the 

 organs of a pig, dried 18 months. I have noted my observations on 

 reactions in mixed bloods (1. vn. '01) on p. 140. Uhlenhuth found that 

 wash-water, containing carbolic acid, sublimate, and soap, gave positive 

 reactions with anti-human serum when it contained human blood, the 

 same being the case with blood containing 3 / borax, and blood-soaked 

 garden earth after the expiration of 3 months. 



The observations of Dr Graham-Smith, in this laboratory, do not 

 confirm the results of Uhlenhuth's tests in the presence of carbolic acid, 

 and of soap (see p. 82). 



The fact that monkey bloods give similar, though less reactions than 

 human blood upon the addition of anti-human serum, may not be a 

 matter of any importance in most countries, where monkeys are not 

 indigenous. Nevertheless it might happen that a murderous organ- 

 grinder, or perchance a similarly inclined keeper of monkeys, backed by 

 a well-instructed defence, would claim that suspected blood-stains were 

 not human but derived from a monkey. On the other hand, Mr Hankin 

 of Agra informed me, as stated in my paper of 21. xi. '01, of a case in 

 India which had come to his notice, where it appeared essential to make 

 a test to determine if certain blood-stains were caused by human or 

 monkey blood. As I stated at the time, it would be necessary in such 

 cases to be provided with an antiserum for the most prevalent genera 

 or species of monkeys belonging to such a region. My tests with anti- 



N. 25 



