under pressure at Temperatures below 32° F. 437 
The prism of ice remained in the clamps with only moderate area contd 
nearly twenty-four hours. The joint was firmly knit at the end of that 8, 
ting with a d in, showi i 
tra ng clear ok 
Proof that the union is not due to atmospheric pressure is furnished by the great 
ease with which the joint is separated when the pressure has been applied only a 
ites 
FUBRUARY 8th, 1869. Rahat tye OAs M. 2° Fl PM. 19° F. 2.15 Pie 
20° F.,4P 22° F., 6.30 Pp. mM. 20° F., 9.15 a. M., sf Feb. 9 9th, 21° F., 10,30 a. M. 
4° FF ighes Da fine block of ice two inches square was 
secured in clamps at 9 A. M. sed experiment at 10.3 f the 
am 
9th. e block separated on the joint with difficulty under a smart blow. 
Feb. 21st, 1870.—Temperatures, aa P.M. 21° F.; 17.30 Pp. uw. 12° B., 7 A. M., of 
Feb. 22d, 6° F, 2p. M. 13 F., ‘3 P, 6° 2 _ Highest temperature 21° F. Set 
sete blocks i in clamps and one Witwer ii 
which had stood without pect a pe parted with a light snap and 
readil 
o. 2, twenty-four hours in clamps, was crushed by the pincers in applying 
transve rse strain, and yielded near to, but not on, the old line of fracture. It 
was shiver ed into fragments but the two faces were . firmly adhering. 
Nos. d arted readily after lying in clamps twenty-four hours. This my 
otes conjecture to have been due to imperfect adjustment of their faces in plac- 
ing them in the clamps. 
JANUA RY 4th, mak Poa arsierigs ae hy A. M, ss pat ne 1p. Mm. 9° F., 
5 Pp, M. Me 8 
ty 
Me 
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st 
|= a 
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— 
‘ot 
Ke! 
oe 
te bS 
oe 
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a) 
we 
3: 
a 
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a 
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of the bench by for Then clamped it in two clamps and wrenched it apart. 
t parted only with viotenee, the separation taking place in a new line parallel to 
the old line of fractu 
e following tril i is selected = bait a ‘iy — low ay of temperatures, 
Gee RY be —Tem mbes 11 Ao a ae a a 8 Pe, 
°F. 6 P, u. 9° Fr, ah a oF Highest rent a 12° oan Three ice prisms 
aio tested i in nthe clamps ear 11 A, M. and 12 noon = 10 
Two of them rosa on aman force. The third required much mor 
force, about the would be required to break a prism of the same ie 
separation, the Fhetices of the old joint presented the torn, ragged appear: 
part. 
e note here she gor that the success of t ting 
oe joint of the b n prism properly Seadjusbed. so as to os the 5 aphtied pres- 
ure bear Hone eid a Dat points — seg eee Failure to do this accounts for the 
feiertect adherence of some spec 
JANUARY 18th, 1871 —Temperatares, This day before noon pi ae 
ranged from 16° F. tol pe um. 16° F., 4 Pp. Mm. 15° F., 10 vp. . 6° F. 
19th, 7.30 a. w. 0° F., Bes noon ve: ze M. 22° ¥. ghest p., 22° F 
about A of 18th put two prisms in clamps and continued one of them 
until 4 P.M. of the 19th. One of these much less than a square inch in c 
section, was well united so a lift sixteen pounds weig he prism was 
omewhat cru Vy pi re and gave way elsewhere than on the eigre line 
of fracture under a heavier ht. I finally wrenched the old joint apart, it 
giving way partly in a new direction. 
JANUARY 10th, 1871.—Te emperatures, wea A 10.15 a. Mm. —4° F., 12.15 P.M. 
—2° F, 1.15 p.m. —-2° F.,2.15 P.M, 0° F.,4P.M.0°F, 10P.M. —4°F. Jan, 10th, 
6 a. M. —7° F., 12 noon 8° F., 9.80 P. M. 9° Pr. oe p.m. 8 F., 9.30 P.M. 3° F. 
Highest temp., 9° F. On the 9th between 11 and 12 in the morning put a prism 
of ice in clamps and kept it there oat x of the 10th. It was so firmly reunited 
ai 
that it did no w bj a strain of hoa scierage = addition of 
five Ibs. more pa it. e test de made ring on of the prism 
and lifting a weight attached to the other end. The ai area of thes cross section of 
ent. 
the prism was less than a square inch by actual measurem 
