THE NATURALISTS' COMPANION. 
42 
THE BEAVER. 
(caster fiber). 
In North America formerly the 
beaver was in great plenty, but ow¬ 
ing to the Hudson Bay Company 
its numbers are greatly reduced, 
still in some places it is found quite 
plentiful. Beavers live in colonies 
beside some clear creek or spring, 
although they sometimes build on 
the banks of a lake. To make the 
water at all times deep enough, the 
beavers fell a great number of trees 
on the banks, always taking care to 
fell them toward the water. These 
are cut into logs about three feet 
long, carried to the river and sank 
by means of stones and mud placed 
Upon them. The logsTntended for 
the dam are first stripped of the bark, 
which is carried to their lodges and 
stored up for winter’s use. These 
dams are about twelve or fifteen 
feet thick at the base and two feet 
or so at the top. The lodges are 
curious structures made of mud, 
moss, and twigs mixed together, 
and are very hard, being frozen by 
‘the cold winter, and, as each sum¬ 
mer a new coating is put on, the 
wall becomes very thick, so that the 
beaver is safe from the attacks of its 
greatest enemy, the wolverene, (gulo 
Luscus). The beaver works in the 
night, so that its various movements 
are not very well known; but it is 
known that the beaver does not, as 
was formerly thought, use its tail as 
a trowel for laying on the mud. 
J. Allen, Jr. 
EKR4TA.—-In A. Nevill’s ex¬ 
change, on page 41, the word Gant 
should be Grant. 
Advertisers, give us a trial ‘^ad.” 
PRIZE. 
We will give any three of the 
portraits mentioned on page 46 for 
the best article on the above bird. 
Yellow-crowned Warbler, (dend- 
RCECA CORONATA). 
CORRESPOJfDEJYCE. 
This Column is open free to yearly subscribers only. 
To T. N. M., Boston, Mass.—The 
highest elevation ever reached by 
man in a balloon is seven and one- 
half miles. The air was so thin at 
that great height, and also so cold, 
that the men in the balloon,Glaisher 
and Coxwell, only escaped by a su¬ 
perhuman attempt. J, Allen, Jr. 
W. G. T., Plymouth,Conn.—We 
accept you offer with thanks 
J. N. A., Lake View, Ill.—Yes, 
it is very easy to identify birds’ eggs 
by tiae use of Davie’s Egg Check 
List. You can obtain the paper 
by addressing H. M.Downs,Rutland, 
Vt. The mineral you sent for iden¬ 
tification is fiberous asbestos. We 
have no idea as to the worth of a 
silver sward plant, still it must be 
very valuable. 
R. D. G., New Sharon, la.—-The 
following description of the Am. 
Goldfinch or Yellow-bird we take 
from Davie’s Check List: “This 
