te 
384 Miscelianies. 
“ Experiment 1.—The length of thirty bricks was placed upon a 
fulcrum, or prop, as nearly in its centre as would admit of the project- 
ing ends being in equilibrium: fifteen bricks were overhanging each 
side of the prop, and after being left in that situation for a length of 
time, it was ascertained that no sensible change had taken place in any 
of its parts. 
“« Experiment 2.—We next placed one end of the connected bricks 
upon a firm support, and then placed heavy weights to keep that end 
down, leaving twenty-two bricks projecting horizontally, quite unsup- 
ported except by the tenacity of the cement; this projection measure 
four feet one inch; the average weight of the bricks was five pounds 
each. After fifteen minutes thus suspended, the extreme end appeared 
to have descended near half an inch, but of this we were not quite cer- 
tain: no further change was at all perceptible. 
“« Experiment 3.—This experiment was both unintentional and un- 
satisfactory ; the workmen in removing the bricks to rest each end 
upon a prop, that we might place weights upon its unsupported mid- 
dle, let one of the ends fall with its full force upon the ground, while the 
other end remained supported : a fracture was the consequence, but it 
was a brick that broke and not the cement. 
Experiment 4.—Ten bricks in length were supported at each end, 
and the weight of 150 kilograms, upwards of 300 pounds, was placed 
upon the middle, and was allowed to remain fifteen minutes without 
undergoing the least change ; additional weights were then added till 
they amounted to 303 kilograms, or upwards of 606 pounds, and af- 
ter being exposed to this weight for ten minutes it broke at the mid- 
dle brick; but, as in the third experiment, it was the brick, and not 
the cement, that had given way.’ pp. 9, 10. 
After quoting an instance or two of the use of this material as @ 
pavement, we must close our notice, and refer those who wish further 
The following are the prices at which Yorkshire stone-paving can now be ob- 
tained in the metropolis 
Tooled. Rubbed. 
a ov dd. 
8 scies 
. Three _ pened per foot re t Epcos i 09 01 
Four inc - 10 1 2% 
The iis ove are the prices os i small sized ‘Sie: ; but where larger stones 
are required, such as are now employed for paving the bettermost streets, the York- 
shire landings must be used, the prices of which are as follows : 
Tooled. Rubbed. 
; s. d. s. d. 
_ Four inch, per foot superficial «te ee a 
iveinch ditto Ss Dit Rages cto aaa ee ey ee 
210 3 2 
inch Pee. ditto * - 7 ” - - = - 
