The effect of anaesthetics upon the human system, as evidenced by spectroscopic observations : read at a meeting of the American Dental Convention, the Southern Dental Association, and the Dental Society of the State of Maryland and District of Columbia, in joint session at Oakland, Maryland, August 16, 1877 / by S. Waterman.

  • Waterman, S. (Sigismund), 1819-1899.
Date:
[1877?]
Catalogue details

Licence: Public Domain Mark

Credit: The effect of anaesthetics upon the human system, as evidenced by spectroscopic observations : read at a meeting of the American Dental Convention, the Southern Dental Association, and the Dental Society of the State of Maryland and District of Columbia, in joint session at Oakland, Maryland, August 16, 1877 / by S. Waterman. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    moment when all carbon is burned out of the iron, or the cast is lost. When this exact moment has arrived, the operation must be stopped instantly; ten seconds more or less will destroy the entire cast. The spectroscope shows this exact moment when the process is finished, and makes the manufacture of Bessemer steel at once an easy and successful task. I think I have touched, like Ithuriel's spear, lightly upon the most salient, technical points necessary, so that you may un- derstand, in how varied a manner, the spectroscope may be utilized. We come now to its application in medicine, and I claim that its usefulness and importance here is second to none I have already mentioned. But to understand how it can show us the effect of anaesthet- ics upon the human system, we must be familiar with the con- stitution of the blood, and learn the optic relations of this vital fluid to the spectroscope, in health and disease. The optic phenomena of blood were not known prior to 1864, when almost simultaneously, Hoppe Seyler, in Tubingen, Ger- many, and Dr. G. G. Stokes, in England, investigated this subject. Stokes pointed out the fact that blood causes a peculiarly strong absorption of light in the yellow and green part of the spectrum. In order to observe this absorp- tion well, the blood should be properly diluted, for in its concen- trated state, the absorption bands between D and E, cannot be observed at all. These two bands are beautifully dark or black, the first which is narrow, more so than the second, which is broader; both are known as the spectral bands of oxidized blood. But blood can exist in a double state of oxidation; that is, it may also exist in a state of complete de-oxidation. The oxidized blood corre- sponds to the arterial; the de-oxidized to the venous blood. When the blood is de-oxidized, the two bands disappear, and are replaced by one dark, broad band, known as Stokes' reduction band. This black band filling the space between D and E, ap- pears whenever the blood is deprived of its oxygen, which it loosely binds.