Come over here now!” He seized me by the coat-sleeve in his eagerness, and drew

me over to the table at which he had been working. “Let us have some fresh

blood,” he said, digging a long bodkin into his finger, and drawing off the

resulting drop of blood in a chemical pipette. “Now, I add this small quantity

of blood to a litre of water. You perceive that the resulting mixture has the

appearance of pure water.

 

The proportion of blood cannot be more than one in a million. I 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 jar.

 

“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.”