264 BULLETIN OF THE BUSSEY INSTITUTION. 
No. 24. — Haperiments on feeding Mice with Painter’s-putty 
and with other mixtures of Pigments and Oil. By F. i. 
STorER, Professor of Agricultural Chemistry. 
I HAVE often speculated as to the cause of the white color of the 
dung of mice, as seen in buildings where the animals have little or 
no access to their usual forms of food. Such dung is particularly 
noticeable in and about churches, lecture halls and school houses ; 
especially in the cellars and lumber rooms of such buildings ; and 
it may often be seen in greenhouses also and in unoccupied dwell- 
ing houses. 
At one time, on the occasion of finding large quantities of the 
white dung under circumstances which suggested that the animals 
might have eaten chalk from the trough of a school blackboard, 
I was led to infer that starving mice may perhaps sometimes eat 
mere chalk as a means of distending their stomachs and allaying 
the cravings of hunger, like the savages in various parts of the 
world, who, as travellers tell us, occasionally resort to ‘*‘ dirt- 
eating.” It would appear, however, that this supposition is not 
correct, at least not for the generality of cases, and that the real 
source of the white mouse-dung is common painter’s-putty, which 
is so largely used in the construction of houses, not only for 
cementing the glass of windows, but for covering the heads of 
sunken nails in boards that are to be oiled or painted, as well as 
for stopping all manner of cracks and holes in wood-work. ‘This 
putty is prepared by mixing ground chalk (the so-called whiting) 
with oil, either linseed-oil or that from the fish known as menhaden 
or pogy, — and it is the oil in the putty which attracts the mice 
and serves them as food. 
I was led to the knowledge of these facts by the following acci- 
dental observations. Having had occasion to employ some work- 
men in a dark cellar at the Bussey Institution, I gave them a 
couple of small tin lamps charged with lard oil, each lamp being 
provided with a plain unwoven wick, composed of coarse, loosely- 
spun cotton threads, which fitted rather tightly into the tube or 
-socket at the top of the lamp. At the close of the day’s work the 
lamps were extinguished and left upon a bench in the cellar. But 
next morning, on trying to relight them, it was found that the 
wicks were no longer in the sockets, but that around each lamp 
