Miscellanies. 375 
once to take the liberty of transmitting to the press, and particularly 
the local press, from which so many reports have emanated, an ab- 
stract of a letter I have received from Mr. Crosse, with an account 
of his experiments, in the language of a private communication, (not 
that which he would probably have chosen, had he made the com- 
munication himself,) and without further comment. : 
“ The following is an accurate account of the experiments in which 
insects made their appearance :-— 
“ Experiment first.—I took a dilute solution of silicate of potash, 
supersaturated with muriatic acid, and poured it into a quart basin, 
resting on a piece of mahogany ; a Wedgwood funnel was placed in 
such a manner that a strip of flannel, wetted with the same, and act- 
- ing as a siphon, conveyed the fluid, drop by drop, through the funnel 
upon a piece of somewhat porous Vesuvian red oxide of iron, which 
was thus kept constantly wetted by the solution, and across the sur- 
face of which, (by means of two platina wires connected with the 
opposite poles of a voltaic battery, consisting of nineteen pair of five- 
inch plates in cells filled with water and -1, muriatic acid,) a con- 
stant electric current was passed. ‘This was for the purpose of pro- 
curing crystals of silex. At the end of fourteen days I observed two 
or three very minute specks on the surface of the stone, white, and 
somewhat elevated. On the eighteenth day, fine filaments projected 
from each of these specks, or nipples, and the whole figure was in- 
creased in size. On the twenty-second day, each of these figures 
assumed a more definite form, still enlarging. On the twenty-sixth 
day, each assumed the form of a perfect insect, standing upright on 
four or five bristles which forms its tail. On the twenty-eighth day, 
each insect moved its legs, and in a day or two afterwards detached 
itself from the stone and moved at will. Itso happened that the ap- 
paratus was placed fronting the south, but the window opposite was 
covered with a blind, as I found these little animals much disturbed 
when a ray of light fell on them; for out of about fifty which made 
their appearance at once, at least forty-five took up their habitation 
on the shaded side of the stone. I ought to have added, that when 
all the fluid, or nearly so, was drawn out of the basin, it was caught 
in a glass bottle, placed under a glass funnel which supported the 
stone, and was then returned into the basin without moving the 
stone. The whole was placed on a light frame made for the pur- 
pose. These insects have been seen by many of my friends, and 
appear, when magnified, very much like cheese-mites, but from twice 
