Figure 22.—Knob end spring lancet used on humans compared to a knob end lancet used on horses and cattle. Note the blade guard on the veterinary spring lancet. (NMHT 302606.09 and NMHT 218383 [M-9256]: SI photo 76-7757.)
In contrast to the few attempts made to modify the human spring lancet, there were a large number of attempts to modify the veterinary spring lancets. Veterinary spring lancets can be found with a wide assortment of shapes and a wide variety of spring mechanisms. In the enlarged knob end spring lancet, pushing upon the lever release simply sent the blade forward into the skin. By a more complex mechanism, the blade could be made to return after it was injected, or the blade could be made to sweep out a curve as do the blades of the scarificator. Perhaps one of the earliest attempts to introduce a more complex internal mechanism into the veterinary spring lancets is found in John Weiss’s “patent horse phlemes” of 1828. The first model invented by Weiss was constructed on the principle of the common fleam and bloodstick. As in the knob end spring lancet, the spring acted as a hammer to drive the blade forward. In a second improved “horse phleme,” Weiss mounted the blade on a pivot so that the blade swept out a semicircle when the spring was released.[199]
The Smithsonian collection contains a number of different types of veterinary spring lancets. Perhaps this variety can best be illustrated by looking at the two patent models in the collection. The first is an oval-shaped lancet patented in 1849 by Joseph Ives of Bristol, Connecticut.[200] By using a wheel and axle mechanism, Ives had the blade sweep out an eccentric curve. The lancet was set by a detachable key (Figure [23]).
The second patent lancet was even more singular in appearance, having the shape of a gun. This instrument, patented by Hermann Reinhold and August Schreiber of Davenport, Iowa, in 1880, featured a cocking lever that extended to form a coiled spring in the handle portion of the gun. Also attached to the cocking lever was an extended blade with ratchet catches, so that by pulling on the cocking lever, the blade was brought inside the casing and the spring placed under tension. Pushing upon the trigger then shot the blade into the vein.[201] (Figure [24].)
Physical Analysis of Artifacts
The Conservation Analytical Laboratory of the Smithsonian Institution analyzed selected bloodletting instruments and one drawing from the Museum’s collection. Instruments were chosen on the basis of their unique appearance and as representative examples of the major types of instruments in the collection. Six lancets and cases, two scarificators, and one pen and ink drawing were analyzed.
Figure 23.—Patent model, J. Ives, 1849.
(NMHT 89797 [M-4292]: SI photo 73-4211.)