BY ELECTRICITY AND GALVANISM.

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oxigen and hidrogen gases, and the mixture of these gases, may beagain inflamed by the electric spark so as to produce water.

This fact was first discovered by a society of Dutch chemists;and the principal circumstance in tire experiment is, the transmis-sion of electrical shocks, through a confined portion of water.The apparatus employed in this experiment by Messrs. Diemanand Van Troostwyk, is a glass tube, about one-eighth of an inch indiameter, and 12 inches long, one of the ends of which is sealedhermetically, a gold wire being inserted at this end, and project-ing about an inch and half within the tube. About the distanceof five-eighths of an inch from the extremity of this, another wireis to be fixed, which may extend to the open end of the tube.The tube is next to be filled with distilled water, and to be placedinverted in a vessel of the same. When thus disposed, electricalshocks are to be passed, between tire two ends of the wirej throughthe water; and if these shocks be sufficiently strong, bubbles ofair will be formed at each explosion, and will ascend, till the upperpart of the wire is uncovered by the water. As soon as this is ef-fected, the next shock that is passed sets fire to the air; and thewater rises again in the tube, a very small quantity of gas re-maining. Now as hidrogen and oxigeu gases, in a state of admix-ture, are the only ones, that are capable of inflaming by the electricshock; and as there is nothing in the tube, besides water, that canafford them in this experiment, we may safely infer, that theevolved hidrogen and oxigen gases arise from decomposed water.

An improved apparatus, exhibiting the same experiment withless trouble to the operator, has been invented by Mr. Cuthbert-son, and may be seen described and figured in Dr. Pearson'spaper, in the Phil. Trans, for 1797, or in Nicholson's Journal,Yols. 1 and 2.

We are likewise indebted to Dr. Wollastone, for decomposingwater in a more commodious manner than the former methods,which require a powerful electrical machine, and considerablelabour. It is as follows:

Vol. it.

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