The affidavit of William Askew, of Berkeley County, and State of Virginia, sheweth, that he was in the city of Philadelphia, as well as he remembers, in the month of S<'ptember last, when he had an opportunity of seeing what is called the Steam Boat, said to be constructed by Mr. Fitch ; on taking a view of^ which boat, (and from the information of a' gentleman, who appeared to be concerned in the said machine) this deponent is of opinion, the boiler will hold five hundred gallons of water. From what he was informed from the gentleman aforesaid, and from his own view, his opinion is, that the machinery of Mr. Fitch's boat, on a moderate calculation, will, on its present construction, weigh seven tons, exclusive of the quantity of wood necessary for the boiler. This deponent further saith, that he verily believes the machinery of Mr. Fitch's Steam boat must necessarily cost three hundred pounds. -- This deponent hath lately seen the steam boat constructed by Mr. James Rumsey, of Berkeley County Virginia, and believes, from good information, as well as his own opinion on examination, that Mr. Rumsey's steam machinery will not, on its present construction, weigh more than eight hundred pounds, anil may be worked with a very inconsiderable amount of wood or coals, perhaps not more coals in twelve hours than four bushels; and that ?vlr. Piumsey's boiler need have no more water, at one time, than one pint, or perhaps not so much, to keep the machinery in sufficient motion to stem the stream of a river, sufficiently fast to be safe with a cargo of goods. This deponent is well convinced that the whole of Mr. Rumsey's machinery may be made for twenty pounds, nor will it occupy more space in a boat than four barrels of flour.