also to receive back any moneys which he may be entitled to withdraw, and to receipt for the same. A. LINCOLN.
County of Washington District of Columbia SS.
On this 10th. day of March 1849 before the subscriber, a Jus Peace in and for the said county personally appeared the within named Abraham Lincoln and made solemn oath according to law, that he believes himself to be the original and first inventor of the within described improved manner of combining buoyant chambers with steam boats or other vessels and that he does not know or believe that the same has been before used or known; and that he is a citizen of the United States. I L. SMITH, JP
To all whom it may concern:
Be it known that I, Abraham Lincoln, of Springfield, in the county of Sangamon, in the state of Illinois, have invented a new and improved manner of combining adjustable buoyant air chambers with a steam boat or other vessel for the purpose of enabling their draught of water to be readily lessened to enable them to pass over bars, or through shallow water, without discharging their cargoes; and I do hereby declare the following to be a full, clear, and exact description thereof, reference being had to the accompanying drawings making a part of this specification. Similar letters indicate like parts in all the figures.
The buoyant chambers A. A. which I employ, are constructed in such a manner that they can be expanded so as to hold a large volume of air when required for use, and can be contracted, into a very small space and safely secured as soon as their services can be dispensed with.
Fig. 1. is a side elevation of a vessel with the buoyant chambers combined therewith, expanded;
Fig. 2. is a transverse section of the same with the buoyant chambers contracted.
Fig. 3. is a longitud[i]nal vertical section through the centre of one of the buoyant chambers, and the box B. for receiving it when contracted, which is secured to the lower guard of the vessel.
The top g, and bottom h, of each buoyant chamber, is composed of plank or metal, of suitable strength and stiffness, and the flexible sides and ends of the chambers, are composed of india-rubber cloth, or other suitable water proof fabric, securely united to the edges and ends of the top and bottom of the chambers.
The sides of the chambers may be stayed and supported centrally by a frame k,---as shown in Fig. 3,---or as many stays may be