1889.] MICKOSCOPICAL JOURNAL. 205 



found that of those measuring $ £ 00 of an inch, forty-six were from the 

 man and six from the dog ; of those measuring -g^^ of an inch, thirty- 

 seven were from the man and seventeen from the dog ; of those measur- 

 ing ^oo" °f an bich, fourteen were from the man and twenty-three 

 from the dog. It will thus be seen that, although the average human 

 blood corpuscle is slightly larger than that of a dog, the variations in 

 size overlap in measurement so as to make it unsafe to express a posi- 

 tive opinion, where the question is confined to that of human or dog's 

 blood. The blood from the guinea pig is still more difficult to deter- 

 mine in comparison with that of man. 



From careful measurements of the i-ed corpuscles in a given speci- 

 men, if found to average the same as those in man, a positive opinion 

 may be expressed that the blood did not come from the sheep, ox, 

 horse, pig, or goat ; the corpuscles in these animals being so much 

 smaller as to render the distinction easy. 



In the famous Hayden trial held in New Haven in 1879, the late 

 Col. J. G. Woodward, M. D., when testifying on the question of blood 

 stains, stated that in measuring twenty corpuscles from one dog, forty 

 from another, and fifty from a third, he found their diameters greater 

 than the recognized average in human blood. On cross-examination 

 by the State he, however, admitted that he had selected only the largest 

 corpuscles for measurement. Subsequently, Dr. Woodward continued 

 his investigations and published the measurements made of red cor- 

 puscles in dog's blood, selecting, as in the Hayden trial, only the largest. 

 This unfortunately renders his data valueless for reference as to averages. 



The blood corpuscles of all birds and reptiles are elliptical in shape 

 and nucleated. This distinguishes them at once from the blood of a man 

 without recourse to micrometry. 



Numerous cases have been recorded where blood stains have been 

 found on clubs alleged to have been used in murderous assaults, where 

 it was claimed as a defence that the stick had been used for killing 

 pigeons or chickens, and where the microscope demonstrated beyond 

 the question of a doubt that the blood could not have come from such 

 source. 



An interesting case in my own experience is worth relating in this 

 connection : Two winters ago in the far northwest, a merchant, prom- 

 inent in the community in which he resided, left his home one evening 

 for the ostensible purpose of visiting his store to transact some unfinished 

 business. Not returning home when expected, his friends became 

 alarmed and went to look for him. On I'eaching 'his store they were 

 startled to see everything in confusion ; furniture broken and strewn 

 about the office ; the safe door open ; money drawer on the floor and empty, 

 save for a few small coin ; blood spattered here and there, and everything 

 indicating a severe struggle, murder, and robbery. Spatters of blood 

 were traced outside into the deep snow which covered the ground ; foot- 

 steps were crowded here and there, and the trail bore indications of a 

 bleeding body having been dragged to the river not far distant, and a 

 hole large enough to admit it chopped through the ice to the swift cur- 

 rent below. It would be hard to conceive a sti'onger case of circum- 

 stantial evidence. 



The man had a large sum of insurance on his life, and a prompt in- 

 vestigation by the insurance companies solved the mystery. A micro- 



