US214101A - Improvement in construction of sharpie-boats - Google Patents

Description

T. OLAPHAM. Construction of Sharpie Boats.

Patented April 8,1879.

ATTORNEYS,

- WITNESSES:

vK PETERS, PNOYO-UTNDGRAPNER. WASHINGTON D C.

UNIT D STATES PATENT OFFICE- THOMAS OLAPHAM, OF ROSLYN, NEW YORK.

IMPROVEMENT IN CONSTRUCTION OF SHARPlE-BOATS.

Specification forming part of Letters Patent No. 214,101, dated April 8, 1879; application filed January 25, 1879.

To all whom it may concern:

Be it known that I, THOMAS CLAPHAM, of Roslyn, in the county of Queens and State of New York, have invented a new and useful Improvement in Sharpie-Boats, of which the following is a specification.

Figure 1 is a longitudinal elevation of the improved boat. Fig. 2 is a plan of its bottom. Fig. 3 is a section through 00 m. Fig. etis a section through 3 y.

Similar letters of reference indicate corresponding parts.

The object of this invention is to provide a staunch seaworthy boat or sailing-vessel of very light draft, which shall present suficient lateral resistance to the water to prevent her making leeway while under sail and closehauled, and which shall not be liable to keel or careen when lying aground.

The ordinary sharpie is a flat-bottomed boat, with a center-board which can be raised to be flush with the boats bottom or lowered at will, and which answers the purpose of a keel.

The well or casing of a center-board occupies a great deal of the most valuable room amidships, and the center-board itself, besides being heavy and requiring much skill and labor for its management, must, in order to make a boat weatherly, project below the boats bottom so much as to deprive the boat of the advantages of sailing on the wind in shallow waters.

The bottom of the sharpie is flat from stem to stern, its profile being indicated by the line a and its prolongation aft, Fig. 1. A sharpies stem is perpendicular and its sides flat. The

flatness of the bottom forward of the midshipsection is the cause of much pounding or spanking, as it is called, when the boat is under way under a good breeze.

It is apparent, then, that there are many objections to the present style of sharpie.

My improvement consists in dispensing with the center-board and its attachments or appurtenances, and aflixing as a substitute to the bottom of the boat two or more keels, A A, of metal or wood, or both. By doing this 1 not only get rid of the cumbersome centerboard and recover valuable space inboard, but, the length being the same, I obtain with two keels of half the depth the same area of lateral resistance which the center-board afforded consequently, without impairing the weatherly qualities of the boat-indeed, having improved them-I have gained the advantage of sailing well in shallower waters than before.

Upon a sharpies bottom, from the midshipsection to the stem, I build the additlon shown at B, thus changing the fiat bottom to one whose cross-section is shown in Fig. 3. In addition to this change in construction, I change the perpendicular lines of the cut-water to lines curving forward, as shown at b b, in consequence of which I am enabled to further improve the shape and sailing qualities of the sharpie by giving hollow lines to the bow or entrance, as shown at c c in Fig. 8.

It is obvious that these various improvements must tend to increase the seaworthiness, the weatherly qualities, and the speed of the boat, and to prevent the unpleasant pounding or spanking above referred to.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- A sharpie-boat provided with the attachment or piece B, arranged below the waterline, and extending from the stem to, or nearly to, amidships, as shown and described, to pre vent spanking, and thus enable the boatto always go in stays.

THOMAS OLAPHAM. Witnesses:

U. SEDGWICK,

S. L. STovER.

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