374 W. J. Taylor on Meteoric Iron from Mezico. 
For the forcing back of the mass Minto the boiler: 
42. W',——Mo(p,-py). 
The whole work is therefore: 
1 
(43.) W'=—[m2". —m,%,4+(M+e)e(T,- Ts) ] + mM Uy (p',-P2) 
$M 5U5( Pz —p',)—Mo(p, is +P! o—Po) Hot o( P's —p' 9). 
, and m, which occur herein may be found 
from equations (Xx1II) and (v1), in which it is only necessary to 
substitute in the first the value p’, in the place of p, to change 
in corresponding manner the quantities 7',,7, and u,, and to in- 
troduce in the last the sum M+» in the place of MI will not, 
however, here completely execute the elimination of the two 
quantities m, and m, which is possible by these equations, but 
will only substitute its value for one of them m,, because it is 
more advantageous for calculation to consider the equation so 
obtained together with the two already determined. The system 
of equations which serves to determine the work of the steam 
engine, is therefore in its most general form : 
‘: 
W= [171 —m,r,+Me(7,-T;) 
Fito ty -mwe(T,— 7") 4 mu, (ps-Po) 
‘iv.°% +H ot" o(2'o — 29) —Mo (P'o —Po)- 
Mala +Aus(p' .-P2)=m 1" -+Me( 7-7 n) gt" 9—He( T,-T") 
+ Attyuo(p" —p"9)+AMe(p,-p's) 
mr, ™m 
22 Z's 
T, T, +(M-+- “)c log T, ‘ 
(To be concluded.) 
eed 
ART. XXIX.— Heamination of the Meteoric Iron from Xiquipileo, 
exico; by W. J. Taytor.* 
cog ng agricultural implements. 
In a dissertation on metallic meteorites by Prof. W. S. Clark, 
the following notices of its literature are given:—Ann. des Mines 
Ser. 1, t. 2, p. 887. Gazeta de Mexico, 1784-5, vol. i., pp. 146, 
200. Klaproth Beitriige zur chemischen Kenntniss der Mineral 
Korper, B. 4, s. 101. Sonnenschmit, Beschriebung der vorzug- 
* From the Proceed. Acad, Nat. Sci. of Philadelphia, vol. viii, No. 3. 
