This I directed my wife to make up as soon as possible, and gave her all requisite information as to the particular method of proceeding. In the meantime I worked up the twine into a net-work of sufficient dimensions; rigged it with a hoop and the necessary cords; bought a quadrant, a compass, a spy-glass, a common barometer with some important modifications, and two astronomical instruments not so generally known. I then took opportunities of conveying by night, to a retired situation east of Rotterdam, five iron-bound casks, to contain about fifty gallons each, and one of a larger size; six tinned ware tubes, three inches in diameter, properly shaped, and ten feet in length; a quantity of a particular metallic substance, or semi-metal, which I shall not name, and a dozen demijohns of a very common acid. The gas to be formed from these latter materials is a gas never yet generated by any other person than myself—or at least never applied to any similar purpose. The secret I would make no difficulty in disclosing, but that it of right belongs to a citizen of Nantz, in France, by whom it was conditionally communicated to myself. The same individual submitted to me, without being at all aware of my intentions, a method of constructing balloons from the membrane of a certain animal, through which substance any escape of gas was nearly an impossibility. I found it, however, altogether too expensive, and was not sure, upon the whole, whether cambric muslin with a coating of gum caoutchouc, was not equally as good. I mention this circumstance, because I think it probable that hereafter the individual in question may attempt a balloon ascension with the novel gas and material I have spoken of, and I do not wish to deprive him of the honor of a very singular invention.

On the spot which I intended each of the smaller casks to occupy respectively during the inflation of the balloon, I privately dug a hole two feet deep; the holes forming in this manner a circle twenty-five feet in diameter.