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THE

LONDON JOURNAL
JOURNAL

OF

Arts and Sciences;

CONTAINING

FULL DESCRIPTIONS OF THE PRINCIPLES AND DETAILS OF

EVERY NEW PATENT,

ALSO

Original Communications

ON OBJECTS CONNECTED WITH

SCIENCE AND PHILOSOPHY,

PARTICULARLY SUCH AS EMBRACE THE MOST RECENT

INVENTIONS AND DISCOVERIES

IN

Practical Mechanics.

BY W. NEWTON,

CIVIL ENGINEER AND MECHANICAL DRAFTSMAN :

AND BY C. F. PARTINGTON,

OF THE LONDON INSTITUTION.

VOLIV.
[SECOND SERIES.]

London :

PUBLISHED BY SHERWOOD, GILBERT AND PIPER, PATERNOSTER ROW;
SIMPKIN AND MARSHALL, STATIONERS' COURT; AND W. NEWTON,
OFFICE FOR PATENTS, 66, CHANCERY LANE.

1830.

GUTHRIE, PRINTER, 16, SHOE LANE.

THE

London

JOURNAL OF ARTS AND SCIENCES.

No. XIX.

[SECOND SERIES.]

Original Communications.

ART. I.-ON M. A. BERNHARD'S PATENT FOR
RAISING WATER. (See Vol. III.)

To the Editors of the London Journal of Arts, &c. GENTLEMEN,-The difficulties which have arisen in discussing the principle upon which water is raised and discharged by Mr. Bernhard's machine, contrary apparently to received theories upon the subject, induce me to submit the following explanation to the attention of your scientific readers. Taking the fact as stated-that a column of water is discharged á vacuo from a height of forty feet above that of the torricellian experiments-the immediate causes of that result appear not to have presented themselves to your correspondents. Both the causes and the result are perfectly consonant to established theories, and serve indeed to confirm the accuracy of principles founded upon experiments.

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An extensive knowledge of chemistry is of importance to those engaged in the construction of hydraulic and pneumatic machines, in order to insure a proposed effect from the operation of combined causes; without this—a discovery, however valuable, may be deemed rather the effect of accident than the result of intellectual skill.

As I purpose making experiments only the foundation and the conclusion of my argument, I trust my observations may prove conducive to the interests of science, and to the improvement of hydraulic inventors in the principles of their specific branch.

To

Mr. B. supposes "that the column of water in the experiment must have increased more than double" by expansion of the water, by means of heat applied to the column in vacuo. this position you and your correspondent Observator naturally demur-as being "contrary to all established theory, and inconsistent with all previous experiments upon that subject." In order to render it perfectly clear-I will first shew the composition of water, and the effect of fire, in altering its chemical combinations; and then treat of the expansion and elasticity of liquids, and vapors or the mechanical effect produced by the action of caloric.

Pure water, that is, water not containing any earthy, alkaline or metallic solution, can be obtained by distillation only, excepting it be formed from its component principles by means of the electric spark, or by fire. Water is composed of oxygen gas, which is the principle or matter by which flame is supported, and of hydrogen gas, which is a substance highly inflammable. These two substances, when in chemical affinity with a certain portion of caloric, which constitutes the fluidity of the combination, form water. The proportion of these two gases in the formation of water is 85 of oxygen, to 15 of hydrogen gas by weight. If pure oxygen and hydrogen gases be mixed together in a close vessel, they remain unaltered; but upon being fired by a lighted taper, or an electric spark, the whole is reduced

if mixed in the above proportion, to a body of water precisely equal in weight to that of the gases employed.

Now the specific gravity of oxygen gas is .00135, the specific gravity of water being always considered as 1.00000; and the specific gravity of hydrogen gas is about .00010; consequently, the usual bulk of an equal weight of hydrogen is as 135 to 10 of oxygen, or thirteen and a half times greater. Multiply then 15 by 13.5=202.5=the bulk of hydrogen gas to 85 parts of oxygen. One hundred parts in bulk of water, consist therefore of 30 parts of oxygen, and 70 of hydrogen in round numbers.

All water, whatever solution or extraneous matter it contains, is composed of this proportion of oxygen and hydrogen gases. Of the waters used for domestic and hydraulic purposes— snow and rain waters are the most pure, then follow the waters of rivers, lakes, and ponds, (saving alluvial deposits and impregnations); then pump waters; and lastly sea water, which besides mechanical suspensions of various matters-holds in chemical solution different salts to a great extent.

The specific gravity of sea water to river water, is as 1.158 to 1.000; from the greater specific gravity of sea water-ships heavily laden which have performed their voyages well in the have sometimes sunk in rivers.*

ocean,

All waters exposed to the atmospheric air largely absorb it, and retain it with great strength of affinity;—indeed, the entire expulsion of atmospheric air from water is a matter of great difficulty-the fiercest fires only effect this object partially. Carbonic acid, and carburated hydrogen gases impregnate almost all waters, in consequence of the continual decomposition therein of animal and vegetable matters. These gases are likewise strongly retained in chemical solution. These are all elastic compressible fluids, water itself is an unelastic incom

A cubic foot of river water weighs 1000 ounces avoirdupoisto 62.5 pounds. A cubic foot of sea water weighs on the average 73 pounds avoirdnpois.

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