Specification of Charles Stevens : bleeding instrument.

  • Stevens, Charles.
Date:
1861
Catalogue details

Licence: Public Domain Mark

Credit: Specification of Charles Stevens : bleeding instrument. Source: Wellcome Collection.

    4/4 (page 2)
    2 A.D. I860.—N° 2252. Provisional Specification. Stevens New Medico-chirurgical Bleeding Instrument. two-thirds of its height, and also with a button of wood or other material, which is attached by a screw to its upper extremity. A metallic disc made (according to the purpose for which it is intended) of an alloy of lead and tin, or of magnetised iron, either pure or mixed with other metals, terminates the lower extremity of the moveable piston to which it is fixed by a screw. On 5 the outer surface of the disc thirty steel needles (more or less) are regularly & circularly arranged, projecting to a length of about ^th of an inch. These needles also may be magnetised, or they may be plated, gilded, or otherwise, to prevent oxidation. At the spot where the upper part of the metallic piston rises above the double cylindrical body a moveable metallic ring is placed, in 10 which the piston passes. This ring serves in case of need to check the advance of the needles in the same manner that the screw of the wooden button serves to increase it. In the interior of the cylindrical body or case, and between the fixed rundle and the upper part of the lower cylinder a spiral spring of metal is placed, and on pressing the button of the piston an alternate 15 movement of compression and extension takes place by aid of the fixed rundle, causing the points of the needles to advance and draw back successively. To obviate the inconvenience of rotations taking place in the action of the piston & disk, the lower part of the rod of the piston is furnished with two or three projecting mouldings, which fit in an equal number of grooves or notches 20 in the edge of the orifice at the top of the lower cylinder, where they can slide regularly, and without deviating from the perpendicular movement, facilitating also the screwing and unscrewing of the button at the top of the piston. LONDON: Printed by George Edward Eyre and William Spottiswoode, Printers to the Queen's most Excellent Majesty. 1861,