118 DE. JOULE ON SOME THEEMO-DYNAMIC EEOPEBTIES OF SOLIDS. 
was clamped to a firm support, aud the 1° J 
35 lbs. On applymg an addrtional tension of ^00 ^ ^ 
ther_ltiplier indicat^^^^^^^^^^ "^n of seveml trials gave me 9'-87, the 
extent indicated the evolntio • „ i-np i unction in water of various tern- 
thermal value of which, determined by immersmg the jun ^.^1 with its 
oi QRA Owine- to the large surface of the woon as couipciic 
pexatures was -OlSel. g ^ -e^ture of the surrounding atmosphere 
capacity for heat, it was a ^ ^ • n otcil T found in fact, that duimg 
nearly three times as much as the quarter-inch m ' thermal effect was 
the time occupied by a swing of the nee e wz. ’ thermal effect. 
:Sch,T5— erer^t conduction of a small 
"tri" to a"i“e Itltlcres “ L necessary to determine the spe- 
•fie hea“ 0 te woTd in the condition it was in when used. This was done by rarsmg 
:h"etatme:f a faggot of it in a bath of mercury, and ‘'^cn^^ ^rn 
filled with mercury at the atmospheric temperature. The iaU ol tempeiatiue 
forryyrl to >10 -3962 aud in that of dried hay wood, -o&b^. r ■ j 
"“s T^ «^hermal effect of tension in the foregoing e.penment, derived 
from'the above data and the expansion by heat at the mean tension, rs 
1 1 - - 
279-4 -200 i__ _J_w_L-^_.o°-02322. 
H=y|^X -y- X 231053 -3962 ^ -0189 
iOJ7V/ 
89. Bas lfood.-The rod I was dried jtil H 
This, increased one pter, gives -0594 as the 
-r “ .. .. 
wood, and its expansion by heat at the mean tension 2o5 lbs., is 
> 1 v-^=-0°-06016. 
■ 196^ ^ -3582 ^ -01886 
278 -400, 
^""1390^ 
91 «. Johns Fine, mt aoross the ym».-This ^Pcc^cn wns dried slowly umiHt 
became electrical by rubbing. A tensile force of 14 lbs. P'°^ce =i * 
indicating a thermal effect of '00494. This, increased by one quarter, ,ir 
cold produced by the tension. The theoretical result is 
H= 
276 —14 
1390 
X 
^ _1_ V y _J— = -0°-0093. 
^ 23256 ^ -3962 -03214 
92. Bay Wood saHraied with water. -Doe "P“ific ?|wvity onhis^specmen ^ 
it weighed 333 grains per foot, 167 grams being im i e w . 
exper-^ents gave me -0073 of heat on applying a tension of 200 lbs., and 
