Scientific Intelligence. — Chemistry. 149 



exhalation of the animal from which the blood was taken. III. In 

 the blood this volatile principle is in a state of combination, its odor 

 being then insensible. IV. When the combination is broken, this 

 principle is volatilized, when it is easy to recognize the animal to 

 which it belongs. V. In each species of animal, this principle is 

 more decided, or has more intensity of odor in the male than in the 

 female ; and in men, the color of the hair accompanies certain varia- 

 tions in this principle. VI. This principle is in a soluble state in the 

 blood, and may be found, therefore, either in the unaltered blood, or 

 after the fibrine has been removed, or even in the serosity of blood. 

 VII. Of all the means of setting this principle at liberty, concentrated 

 sulphuric acid has succeeded best. 



To obtain these results, it is only necessary to put a few drops of 

 blood, or the serosity of blood, into a glass, to add concentrated sul- 

 phuric acid, to the amount of one third or half as much as of blood, 

 and to stir the whole together with a tube : the odoriferous principle 

 is immediately rendered evident. By these means, M. Barruel can 

 readily distinguish the blood from the following sources. 



1. That of a man disengages a strong odor of the perspiration of 

 man, which it is impossible to confound with any other. II. That 

 of a woman by a similar odor, much weaker, and resembling the 

 perspiration of women. III. That of the ox, a strong odor of oxen 

 or a cow-house, or of cow-dung. IV. That of the horse, by a strong 

 odor of the perspiration of the horse or of horse-dung. V. That of 

 a ewe, by a strong odor of wool, impregnated with the perspiration 

 of that animal. VI. That of a wether, by an odor analogous to that 

 of sheep, mixed with a strong odor of the goat. VII. That of the 

 dog, the odor of the transpiration of a dog. VIII. That of a pig, by 

 the disagreeable odor of a piggery. IX. That of a rat, by the bad 

 odor belonging to the rat. 



The same result has been obtained with the blood of various kinds 

 of birds ; and even with the blood of a frog, which gave the strong 

 odor of marshy reeds, he. ; and with that of a carp, which gave a 

 principal smelling like the mucus which covers the bodies of fresh 

 water fish. 



Upon trials made to ascertain whether spots of blood could be dis- 

 tinguished, and referred to their source, M. Barruel found, that to a 

 certain extent, a pretty sure judgment could be given, even after 

 fifteen days or more. The spotted linen is to be cut out, put into a 

 watch glass, and being moistened with a little water, is to be left for 



