Lewis fob attaching tackles to blocks of stone
US 22551 A
Description (OCR text may contain errors)
UNITED STATES PATENT OFFICEB EUGENE DUCHAMP, OF ST. MARTINSVILLE, LOUISIANA.
LEWIS FOR ATTACI-IING TACKLES TO BLOCKS OF STONE.
Specification of Letters Patent No. 22,551, dated January 11, 1859.
To all whom t may concern:
Be it known that I, EUGnNn Dn'cHaMr, of St. lVIartinsville, in the parish of St. Martin and State of Louisiana, have invented a new and Improved Lewis for Attaching Tackles to Large Blocks of Stone or other Objects; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the annexed drawings, making part of this specification.
Figure l, is a vertical section of the improved lewis attached to a block of stone, with the air pump for exhausting the air therefrom applied to its side. Fig. 2, is a top or birds eye view of ditto, with the air pump detached. p
Similar letters in the figures refer to corresponding parts.
To enable others skilled in the art to make and use my invention I will describe its construction and operation.
The shell A, may be made of metal or other suitable material, of a semi-spherical, or segment of a sphere, or parabolic form, and is provided with a nozzle or tube B, on one side, in which is formed and attached a cock C, for opening and closing the communication through said nozzle or tube B. To the outer end of this nozzle or tube is attached by a screw, which enables it to be attached and detached at pleasure, an ordinary air pump D, arranged at a convenient angle of inclination .in relation to the surface of the shell and the object to be raised, to enable the air within the shell to be readily exhausted therefrom when properly placed upon the surface of said object.
Between the circular or parabolic edge, as the case may be, of the shell and the surface of the block of stone or other object, it is intended to hoist, is arranged a circular ring of india rubber or leather E, previously saturated with oil or other unctuous substance to make it pliable, larger in capacity than the area of the surface covered by the base of the shell, in such a manner as to enable the said piece of leather or gum to be pressed into the pores of the stone H, or other object, by the edge of the shell, which is thus made to conform with the slight inequalities usually occurring on the upper' surfaces of building stone and the other heavy objects usually raised by the ordinary lewis.
Then it is desired to raise a stone with this improved form of lewis, the shell A, with the circulaiI piece of leather E, or gum elastic, below its edge, is placed upon the center portion of the surface of the stone or other object, and after the air pump D, is screwed firmly to the nozzle or tube B, of the sam-e, it is pressed upon the said surface with the required degree of force `to press the leather ring E, into the pores of the stone or other object and thus form an air tight joint around the said edge. The air is then exhausted from the shell by the air pump and the cock C, .is closed, and the pump is detached from the nozzle or tube, leaving the shell firmly attached to the surface on which it bears with an adhesive power equal to the pressure of the exterior atmosphere over the entire surface covered by the shell, the extent of the area covered, and consequently the size of the shell, being regulated by the weight of the article to be raised. The hook of the tackle or lifting chain F, or rope, is then attached to the ring, staple or eye G, fastened to the apex of the shell, and the said block of stone or other object is raised in the usual manner, without in any manner defacing or in any way injuring the same. Vhen raised and deposited at the required height the cock C, is turned so as to let the air into the interior of the shell through the nozzle or tube B, which at once destroys the vacuum and detaches the shell from the lifted body.
Having thus described my invention, I claim and desire to secure by Letters Patent, as an improved article of manufacture.
A lewis, composed of a shell A, air pump D, nozzle or tube B, packing E, staple G, and otherwise made as shown and herein described,
Titnesses HENRY WALES,