TERRA-COTTA, BRICK, ETC.
329
Table showing the Percentage of Water absorbed by various Bricks after Thirteen Days' submersion.
Ù
•o
g
&
Degree of Burning.
Locality of Clay.
The Process of Manufacture.
Weight in pounds
and ozs. before
submersion.
Weightinpounds
and ozs. after
submersion.
Gain in weight
in ounces.
Percentage of
whole
weight gained.
1
Hard, . .
Pea Shore, N. J., .
Chambers’ machine,
5 0
5 2
2
2.5
2
Dark, . .
a a a
a a
4 15
5 7
8
10.12
3
Light, . .
a a tt
a ti
4 14
5 10
12
15.4
4
Salmon, .
a a a
a a
4 14
5 12
14
17.95
5
Very hard,
t< u a
Hvd. Press, 600 tons
pressure,
2 4
2 6
2
*5.55
6
Dark, . .
a a a
Dry Press,
4 13
5 7
10
13.
7
Salmon, .
<( a a
Dry Press,t
2 8
3 1
9
22.5
8
Dark, . .
Hestonville, Phila.,
Chambers’ machine,
5 3
5 15
12
14.46
9
Dark, . .
<< <<
i( it
5 5
6 3
14
16.47
10
Light, . .
it U
a a
5 3
6 0
13
15.66
11
Salmon, .
u a
a a
5 8
6 8
16
18.18
12
Salmon, .
a a
Hand,
4 8
5 8
16
22.22
13
Light, . .
a a
« ...
4 10
5 8
14
18.91
14
Hard, . .
a a
it
4 12
5 8
12
15.78
15
Salmon, * .
Neck, Phila., .
<<
4 8
5 7
15
20.83
16
Light, . .
it «
<( ...
4 13
5 9
12
15.58
17
Hard, . .
tt a
a
4 11
5 2
7
9.33
18
Hard, . .
“ u
a
4 10
Ö ö
9
12.16
19
Dark, . .
Hudson R., N. Y.,
Hall’s machine,
4 3
4 6
3
4.47
20
Light, . .
« « «
<C it
4 2
4 12
10
15.15
* This brick, in the process of manufacture, was submitted to a pressure under a hydraulic press of 221,695 pounds to the square inch.
t This brick was made by the dry-clay process, of the same clay as No. 1, and was exposed one winter to the action of the frost, and had partially fallen, none of the angles being left.
This shows a gain in weight of from two to sixteen ounces, or from 2 \ per cent, to 22 \ per cent.
The capillary power of bricks is such that even if made hollow in the best manner, the inner surface must become as fully saturated with water as the outer; and there is no remedy except to protect the outer surface by an impervious glaze, or enamel, or to thoroughly isolate the inside wall, or layer, from contact with the outer. Even headers, or tie-bricks, at intervals, serve to convey the moisture and destroy the efficacy of a hollow wall.
Sizes of Bricks.
There was a variety of sizes of bricks shown at Vienna. In general, they are broad and not thick. In the United States there is no standard size. In the Eastern States bricks are short, narrow, and very thick. The latter make a 42