The disintegration of organic tissue by high tension discharges / by J. Inglis Parsons.

  • Parsons, J. Inglis, 1857-1928
Date:
1895
Catalogue details

Licence: Public Domain Mark

Credit: The disintegration of organic tissue by high tension discharges / by J. Inglis Parsons. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    19/21 page 14
    15’6; and at six inclies 27‘0, We thus see that with the needles six inches apart the current has twenty-seven times more tissue to disintegrate than when they are two inches apart. In order to make up for this the pressure and the number of interruptions must be increased in a similar proportion. When describing the drawbacks of a transformer, I pointed out that in the opinion of leading electricians a transformer does not develop against a low resistance like beef anything like the pressure which is developed against air. Now the resistance of the beef used was only 220 ohms. I therefore tried the effect of interposing an air gap Ij inches in the circuit. By this means a pressure of at least 30,000 volts must be developed to spark across the air gap. A similar experiment was tried with a vacuum tube in the circuit instead of an air gap. On examining sections of beef from the former, I found very little change. The enormous resistance of the air gap probably exhausted nearly all the energy of the current. With the vacuum tube in the circuit, a greater change could be seen. There was some loss of striation and fraying of the muscular fibres. The resistance of a vacuum tube is very much less than air, consequently more energy in this instance was expended on the beef. My next experiment was to try the effect of a Leyden jar as a condenser in conjunction with the transformer. The two poles from the transformer [Demonstration], as I now show you, are connected one with the outside, and one with the inside of the jar. The electricity first charges the jar, and is then discharged. You will also observe that a considerable change has taken place in the character of the discharge. The spark is much thicker, and shorter. In other words, the quantity is increased at the expense of the pressure. The spark will not extend much more than three quarters of an inch. The pressure, therefore, is approximately about 18,000 volts. There is also another change. The discharge takes place more
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