154 
Bricks . 
water ; but the less water that is used, the substance of the clay 
will be more tough and gluey, and consequently the bricks will 
bfe smoother and more solid. This operation is the most labori- 
ous part of the process ; but it is of essential importance, and 
therefore ought to be done well ; for it is to the negligence of the 
manufacturers in this respect, that we are to attribute the bad 
quality of our modern bricks, which are often light and spongy, 
and full of cracks Whereas, if the clay be properly tempered, 
they are hard, ponderous, and durable ; much stronger and better 
fitted for every kind of building, than those made in the common 
way. This will appear very evident from the following experi- 
ment of M. Gallon. Having taken a quantity of brick-earth, tem- 
pered in the usual way, he let it remain exposed to the air for se- 
ven hours, and then caused it to be moistened and beaten for the 
space of half an hour : the next morning the operation was repeat- 
ed ; and in the afternoon the clay was again beaten for fifteen mi- 
nutes more ; making the whole additional labour an hour and a 
quarter. The bricks made of this earth being dried in the air for 
thirteen days, and burned along with the rest without any parti- 
cular precautions, were found to be not only heavier than com- 
mon bricks, but also very different in strength ; for on placing 
their centre on a sharp edge, and loading both the ends, M. Gallon 
found, that while it took a weight of 65 lb. at each end to break 
them, other bricks were broken by the weight of only 35lb. The 
improvement in the quality of the article thus far exceeds the ad- 
ditional labour ; and none would hesitate to give an additional 
price, since both the value and the comfort cf our dwellings de- 
pend so much on the quality of the materials of which they are 
constructed. 
The next part of the process is the moulding of the bricks. 
This is a very simple operation, and requires very little skill, un- 
less it be to make the greatest number in the shortest time ; and 
the day’s labour of a handy workman, employed from five in the 
morning until eight at night, is calculated at about 5000. The 
clay is brought to the moulder’s bench in lumps somewhat larger 
than will fit the mould. The moulder, having dipt his mould into 
dry sand, works the clay into it, and with a flat smooth stick strikes 
off the superfluous earth. The bricks are then carried to the 
hack, and there ranged with great regularity one above the other, 
a little diagonally, in order to give a free passage to the air. The 
hacks are usually made eight bricks high ; and wide enough for 
two bricks to be placed edgewise across, with a passage between 
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