ON CERTAIN TRANSFORMATIONS. 101 
magnesia ; no iron or copper.” All these mines are several miles from the sea. 
The water from the deepest level in Levant and Botallack also contained 
‘some common salt, and was slightly saline to the taste; but the proportion 
was much less than might have been expected in excavations extending so 
far under the sea. I have examined the water from numerous mines, taken 
immediately from the springs at their entrance from the veins into the levels, 
and I have not detected the presence of any metal, except in some instances 
a very little sulphate of iron, and traces of the sulphate of zinc, on two or 
three occasions. On the other hand, it may be observed, that the water not 
coming directly from the springs, but which is collected more or less in 
pools in the levels, often contains metallic salts derived from the ores in 
the levels broken from the lodes, and exposed for a time in heaps to the 
joint action of air and water. 
The phenomena observed in mineral veins, however, afford strong pre- 
sumptive evidence that the water circulating through them has, from time to 
time, varied much in its properties, sometimes depositing minerals, and at 
others decomposing them. 
Captain J. Puckey has, at my request, made an experiment on the tem- 
perature of the rock at the end of a “cross-cut” in Fowey Consols. The 
end was dry, 60 fathoms from the lode, distant from other workings, and 140 
fathoms deep. He thinks that they will have to extend the cross-cut 20 
fathoms further to intersect another lode. The thermometer remained an 
hour in a hole of the rock, the top of which was closed with clay; and on 
being withdrawn, the mercury was found at 82°, and in the air it stood at 78°. 
Captain John Kitto has also made experiments in Swanpool lead mine near 
Falmouth; temperature of rock 58° at the end of a dry cross-cut, 34 fathoms 
northward of the lode, and 55 fathoms deep. In another cross-cut, the end 
of which is 14 fathoms to the south of the lode, and 60 fathoms below the 
surface, the rock was at 60°, air 64°, and the water 59°. The presence of 
the latter probably indicated the proximity of another lode. This mine is 
80 fathoms deep, and both the mines are in killas. 
I may remark, in conclusion, that on comparing the specific gravities of 
pieces of different rocks taken from the deepest parts of some of the mines, 
with others of the same kind occurring at or near the surface, I have not 
found any decided differences between them in this respect, 
—2 aflt1gil+) gilt} 
fe at, AC ee 
0 pilttyty ata 
De quelques Transformations de la Somme 2 
entier négatif, et de quelques cas dans lesquels cette somme est ex- 
primable par une combinaison de factorielles, la notation atl* désig- 
nant le produit des t facteurs a(a+1)(a+2) &c....(a+t—1). Par 
G. Puarr, Docteur és Sciences de Strasbourg. 
[A Communication ordered to be printed entire among the Reports of the Association: ] 
- Dans un mémoire sur la série 
a. a.p a(a+1)6(B+1) adl+igalt ie 
Gauss a donné une expression de lasomme de cette série pour des valeurs 
