under pressure at Temperatures below 32° F. 441 
of the following phe ald the ieee press, excepting the first in 
which the screw wa ned by hand, the actual pressure per 
square inch used. "The ae tempe ratures of the room or 
shed in which the work was done are also carefully recorded, 
along with each trial, for every few hod urs of the day or days 
th ae which the trial lasted. With these Srey I give 
the following : 
rat poten on Snow with the Tron Press, 
DECEMBER 29th, 18 0.—Temperatures, Saw OP AP ee ESP. we a 
P.M. 2° F., highest Capac aden e3°F. At9o’clock a. M. packed the mould with snow 
screw at a time, so as to avoid evolving heat in the snow by sudden pressure. At 
noon the force necessary to turn the screw through the quarter had become con- 
siderable, though by no means violent. The screw was turned slowly through 
the abi arter. Thus three hours were consumed in bringing the strong pressure 
to 
_ Discontinued the experiment at 7 P. The w was converted akg 
to perfect ice, white, clouded here with darker an’ share with lighter lnes— 
aceak: This ¢ experi riment is a perfect success. Everything has been adage 
care, 
January 4th, 1871.—Temperatures, 8.15 a. Mm. 2° F., ee mo FF M. 9° 
PUD SG i” 1p ale BF, 10Pp.M. 8° F., 64. M., January 5th, 15 12.30 P. 26° F. 
eft stan 
through the night, but the wheel Lion turned petites beg d about a quarter crcl 
during the whole night. This I think is the most pe rmed as yet 
at low temperatures or under slowly applied pres vi ‘tt was perfect gray ice 
uniform throughout, n ouded. 
JANUARY ou 1871 —emperatares 0.15 a.m. —4° F., 12.15 —2° F., 1.15 p. . 
—2°F.,2.15 p.m. 0°F., 4 0° F., 10e.m.—4°F, January 10th, 6 a.m. —7° F., 
9.30 A.M. 0° F, ‘highe est psig 0° F. ape ney pressure at 10. 15 A. M., after 
d for 
. Com- 
menced with weight of three pounds aoe 375 Ibs. Aine and then added 
two pounds, ete. Discontinned at 9.30 A. M. of the ts the Arora marking 
0°. Highest weight u 60 Ibs. =412 . Pp re per inch. Result 
ata mass changed to py throughout of panama ay at every way fine 
uality. The weight was increased very gradually, only a few last additions 
ght 
being weve in quantities sabe 6 or 8 Ibs.=400 to 550 Ibs. pressure. At this point 
the me very slow. e press was left over night with a weight of 60 
tba -4123 Ibs. sda per square inch, and the screw did not probably make 
mm during the ~~ and up to the time of Seaiie the trial. 
The snow used was slightly gran 
JANUARY 18th, 1871.—Themomete: r up to 12 noon has ranged from 16° to 18° F., 
relates 16° F.,4 p.M. 15° F., 10 Pp. M. 6° F. January 19th, 7.30 a, mw. 0° F,, 
pote F., 4p. M. 22° F. Highest temperature to which snow was exposed 
while iis vader pressure was 18°F. The mould was packed with snow last night (the 
* The resulting pressure for each additional oe of power diminishes as we 
go into the higher ‘ee owing to increased fricti: 
