Specification of James Horne : injecting instruments, &c.

  • Horne, James.
Date:
1857
Catalogue details

Licence: Public Domain Mark

Credit: Specification of James Horne : injecting instruments, &c. Source: Wellcome Collection.

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    Hornes Improvements in Injecting Instruments, cfc. expelled from the pump ascends to the top of the water in the case S, and by its pressure on the fluid causes a continuous stream to flow out of the injecting pipe. On finishing the operation care must be taken to close the cock W before withdrawing the pipe. The advantages attending the mode of construction and operation just ^ described, (whether an air pump of the first or second kind described is em¬ ployed), are : — First, that the valve or valves of;.the air pump are of so simple a construction that no length of use can materially impair their efficiency, and that as no fluid passes through the pump no clogging or corrosion of its parts can ever take place from that source, so that from both causes the pump ^ continues at all times clean and fit for immediate use; second, that no air can be thrown forward either at the beginning or during any part of the operation, whereby a frequent cause of complaint, and even of serious injury, where injecting instruments are used, is wholly avoided ; third, that the fluid is injected in a gentle yet continuous and well sustained stream, with no more ia than the exact amount of force required, and that it may cease to be injected the instant its application ceases to be pleasant or useful; and, fourth, that none of the fluid can escape from the apparatus except through the injecting pipe. When the instrument is not in use, it is packed up in the manner represented in Figure 6. The case S is first emptied of the water or other ^ fluid through the orifice T. The pump is then unscrewed and dropped through the orifice T into a circular stand X fixed for its reception in the bottom of the case. The injecting pipe is next taken off and made into two lengths by unscrewing the piece 3 from the piece 2, and these lengths are dropped through the orifice in the top of the case previously occupied by the ^ pump into a second stand Y fixed in the bottom of the case. The two orifices being nowT closed, that marked T with the cap proper to it, and the other with a cap Z kept for the purpose, the top of the case exhibits the appearance represented in Figure 7. The case S, instead of being oval, as represented in Figures 5, 6, and 7, may be made circular with a single opening in the top, having a double screw cap to fit, as shewn in Figure 8. In both the air pumps before described valves are employed, but in Figure 9 I have shewn a form of construction where no valves whatever are made use of, and which may also be applied with advantage to injecting instruments. A is the barrel, B is the piston, C the rod, which works through stuffing boxes at top and 35 bottom, and slides to and fro through the body part to the extent of the space between the two steps a and b. It is hollow throughout with the exception of a diaphragm inserted at d, and is closed at both ends, but has side