wide a one that I have felt compelled to restrict my
remarks to local sandstones, but the general principles of structure
apply to all sandstones alike.
It is difficult by written description to tell you how to select a
good stone, but one essential is that there shall be a good deposition
of secondary quartz, as shown by the crystalline sparkling on the
freshly fractured surface.
It must also be free from very decided laminations, for these
constitute planes of weakness and are often indications of the
deposition of varying materials, or the same material in various
grades of fineness. It must also not be full of argillaceous and
iron-oxide infillings. It should possess a homogeneous texture. The
best way to study building stones is to study them in old buildings,
for nature has then dissected their weaknesses.
FOOTNOTES:
[1] Read before the Liverpool Architectural Society, on the 18th
November, 1889, by Mr. T. Mellard Reade, F.S.G.S. _Fellow_,
President of the Society, and printed in the _R.I.B.A. Journal_.
[2] This experiment was made before the audience.--T. M. R.
* * * * *
WARFARE ON OAK TREES.--"The world seems to have waged a special
warfare upon oak trees," says a St. Louis man. "Before iron ships were
built, and that was only twelve years ago, oak was the only thing
used. When this drain ceased oak came into demand for furniture, and
it is almost as expensive now as black walnut. No one feels the
growing scarcity of oak like the tanner, and the substitution of all
sorts of chemical agencies leads up to the inquiry as to whether other
vegetable products cannot be found to fill the place of oak bark. The
wattle, a tree of Australian growth, has been found to contain from
twenty-six to thirty per cent of tannic acid. Experiments have been
made on the Pacific Slope, where the wattle readily grows, and in a
bath of liquor, acid was made from it in forty-seven days, whereas in
liquor made from Santa Cruz oak, the best to be found in all the
Pacific States, the time required is from seventy-five to eighty days.
The wattle will readily grow on the treeless plains of Texas, New
Mexico and Arizona, the bark of which ought to yield five dollars per
acre counting the fuel as nothing."--_Invention._
THE BARYE EXHIBITION.
[Illustration]
Entering the handsome galleries of the American Art Association, one
finds the lower floor given up to the Barye bronzes, while t
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