have no doubt, however, that we shall be able to obtain the characteristic reaction.” As he spoke, he threw into the vessel a few white crystals, and then added some drops of a transparent fluid. In an instant the contents assumed a dull mahogany colour, and a brownish dust was precipitated to the bottom of the glass
“Ha! ha!” he cried, clapping his hands, and looking as delighted as a child with a new toy. “What do you think of that?”
“It seems to be a very delicate test,” I remarked.
“Beautiful! beautiful! The old Guiacum test was very clumsy and uncertain. So is the microscopic examination for blood corpuscles. The latter is valueless if the stains are a few hours old. Now, this appears to act as well whether the blood is old or new. Had this test been invented, there are hundreds of men now walking the earth who would long ago have paid the penalty of their crimes.”