180 Scientific Intelligence.—Geology. 
only one in eighteen of the shells taken from below 100 fathoms ex- 
hibited any markings of colour, and even the few that did so were 
questionable inhabitants of those depths. Between 35 and 55 
fathoms, the proportion of marked to plain shells was rather less 
than one in three, and between the margin and two fathoms the 
striped or mottled species exceeded one-half of the total number. 
In our own seas, the author observes that testacea taken from 
below 100 fathoms, even when they were individuals of species 
vividly striped or banded in shallower zones, are quite white or 
colourless. Between 60 and 80 fathoms, striping and banding are 
rarely presented by our shells, especially in the northern provinces ; 
and from 50 fathoms shallow bands, colours, and patterns are well 
marked. 
The relation of these arrangements of colour to the degrees of 
light penetrating the different zones of depth, is a subject well 
worthy of minute inquiry, and has not been investigated by natural 
philosophers. —( Proceedings of the Royal Society, March 23, 1854.) 
9. On the employment of water in filling up deep Bore-Holes nm 
Blasting Operations——In working the great deposit of magnetic 
iron ore, which occurs, under peculiar circumstances, in the granite 
at Marovitza in the Banat, it has been found necessary, in conse- . 
quence of the hardness of the rock and ore, to use bore-holes from 
2 to 24 inches in diameter, and 36 to 40 inches deep. The pack- 
ing of such holes with clay being a very tedious operation, Mr A. 
Keszt endeavoured to substitute water in the clay with considerable 
suecess. One of Brickford’s safety fuses, which burns in water per- 
fectly, is attached to the cartridge and fastened with the end; this 
cartridge is let down to the bottom of the hole, and about 12 to 2 
inches of clay firmly packed over it; the remainder of the bore, to 
nearly the top, being filled with water. In the case of very oblique 
bores, where the pressure of the water upon the bottom was small, 
he plugged up the orifice of the bore with a plug of wood driven 
with considerable force into it, through a slit in which the fuse 
passed. More recently still, he has used, instead of the small quantity 
of clay at first introduced to keep the cartridges from being wetted 
by the water, a mixture of tar and pitch, which most effectually pre- 
serves the powder from damp. Great numbers of trials have con- 
vinced him that the blasts fired with this arrangement loose nothing 
in force, whilst there is a very great saving of time and consequently 
of expense.—(Oesten. Zeitschrift fur Berg-u-Hiittenwesen, 1803. 
—WNo. 13. 
10. The American Tunnelling-Machine.—Talbot’s “ tunnelling- 
machine” has been tried, with complete success; and it has been 
demonstrated that mountains of primitive stone, and the hardest 
rocks in the earth, can be successfully and economically tunnelled 
