The electronic variation with strong polarising currents / by G.N. Stewart.

  • Stewart, G. N. (George Neil), 1860-1930.
Date:
[1889?]
Catalogue details

Licence: Public Domain Mark

Credit: The electronic variation with strong polarising currents / by G.N. Stewart. Source: Wellcome Collection.

    15/20 (page 245)
    of nerve in the longitudinal direction is a constant. Of course it will vary slightly even for the two nerves of the same frog, as it will depend mainly at least upon the amount and kind of the dissolved crystalloids. In my former results on the intrapolar elfect I found that the limiting electromotive force varied from 8 to 9 Daniells, when the length of nerve was from 12 to 14 mm. The two sets of experiments therefore agree as well as one is entitled to expect in observations of this sort. The strength of stimulus, of course, has also to be taken into account. Experiments 12 and 13 show how the effect in the extrapolar region reaches a maximum, while in the intrapolar it declines to a minimum. This of itself is quite enough to dispose of the pos¬ sibility that the suppression of the intrapolar effect is due to the decline of excitability at the point of stimulation through the spread of anelectrotonus. Experiment 14 is an example of stimulation on the cathodic side. Fig. 6. Fig. 6 shows the curve of the effect in Experiment 12 plotted to scale. The number of points are too few to determine the details. Almost the whole of the ascent lies very nearly in a straight line.