my laboratory.
However, my ordinary camera will do, for all I want is to preserve a
record of these marks, and I can enlarge the photographs later. In the
morning I will photograph these marks and you can do the developing of
the films. To-night we'll improvise the bathroom as a dark-room and get
everything ready so that we can start in bright and early."

We were, indeed, up early. One never has difficulty in getting up early
in the country: it is so noisy, at least to a city-bred man. City noise
at five A.M. is sepulchral silence compared with bucolic activity at
that hour.

There were a dozen negatives which I set about developing after Craig
had used up all our films. Meanwhile, he busied himself adjusting
his microscope and test-tubes and getting the agar slides ready for
examination.

Shirt-sleeves rolled up, I was deeply immersed in my work when I heard a
shout in the next room, and the bathroom door flew open.

"Confound you, Kennedy, do you want to ruin these films!" I cried.

He shut the door with a bang. "Hurrah, Walter!" he exclaimed. "I think I
have it, at last. I have just found some most promising colonies of the
bacilli on one of my slides."

I almost dropped the pan of acid I was holding, in my excitement.
"Well," I said, concealing my own surprise, "I've found out something,
too. Every one of these finger-prints so far is from the same pair of
hands."

We scarcely ate any breakfast, and were soon on our way up to the hall.
Craig had provided himself at the local stationer's with an inking-pad,
such as is used for rubber stamps. At the hall he proceeded to get the
impressions of the fingers and thumbs of all the servants.

It was quite a long and difficult piece of work to compare the
finger-prints we had taken with those photographed, in spite of the fact
that writers descant on the ease with which criminals are traced by this
system devised by the famous Galton. However, we at last finished the
job between us; or rather Craig finished it, with an occasional remark
from me. His dexterity amazed me; it was more than mere book knowledge.

For a moment we sat regarding each other hopelessly. None of the
finger-prints taken at the hall tallied with the photographed prints.
Then Craig rang for the housekeeper, a faithful old soul whom even the
typhoid scare could not budge from her post.

"Are you sure I have seen all the servants who were at the hall while
Mr. Bisbee was here" asked Craig.

"