"There are two principal methods. One is to stir or whip the fresh blood rapidly with a bundle of fine twigs. When this is done, the fibrin—the part of the blood that causes solidification—adheres to the twigs, and the blood that remains, though it is unchanged in appearance, will remain liquid for an indefinite time. The other method is to dissolve a certain proportion of some alkaline salt in the fresh blood, after which it no longer has any tendency to solidify."
"You have heard the evidence of Inspector Sanderson and Sergeant Bates?"
"Yes."
"Inspector Sanderson has told us that he examined the safe at 10.31 a.m. and found two good-sized drops of blood on the bottom. Sergeant Bates has told us that he examined the safe two hours later, and that he took up one of the drops of blood on a piece of white paper. The blood was then quite liquid, and, on the paper, it looked like a clear, red liquid of the colour of blood. What should you consider the condition and nature of that blood to have been?"
"If it was really blood at all, I should say that it was either defibrinated blood—that is, blood from which the fibrin has been extracted by whipping—or that it had been treated with an alkaline salt."
"You are of opinion that the blood found in the safe could not have been ordinary blood shed from a cut or wound?"
"I am sure it could not have been."
"Now, Dr. Rowe, I am going to ask you a few questions on another subject. Have you given any attention to finger-prints made by bloody fingers?"
"Yes. I have recently made some experiments on the subject."
"Will you give us the results of those experiments?"