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IOWA ACADEMY OF SCIENCE Vol. XXVIII, 1921 
PLATE 11. 
Explanation of Figures. 
1. Typical fatigue curve resulting from stimulation of muscle im- 
mersed in strong methyl alcohol. Note the initial relaxation phase is 
almost lacking, and the temporary stimulating effect as evidenced by the 
height of the first few contractions. 
2. Fatique curve of muscle immersed in SO vol. per cent methyl al- 
cohol. The early relaxation phase is here beginning to be conspicuous and 
is somewhat prolonged. 
3. Typical curve when immersed in 29.1 vol. per cent methyl alcohol. 
Relaxation phase more pronounced, conspicuous treppe, but rather rapid 
onset of secondary contracture. 
4. Curve resulting on immersion in 20.8 vol. per cent methyl alcohol. 
This concentration perhaps may be regarded as lying in a relative range 
of concentration where phases are well balanced in modification. A rather 
prolonged initial relaxation with long constant strokes, a uniform second- 
ary contracture terminating in a reversible decline towards the end. 
5. Curve resulting from ^immersion in the weakest methyl alcohol used, 
12.4 vol. per cent. Somewhat stimulating as evidenced by the early re- 
laxation phase, the height of the excursions and the duration of upper 
margin of the plateau of secondary contracture. 
6. Comparative curve resulting from stimulating muscle in air. Note 
the height of excursions, the initial relaxation phase, and the gradual and 
uniform development of secondary contracture. The whiter area inside 
is caused by the less intense “make” shocks. 
7. Typical strong ethyl alcohol curve. Practically no initial relaxation 
phase, gradual onset of secondary contraction, a conspicuous treppe, and 
a sustained contracture plateau. 
8. Typical curve using 50 vol. per cent ethyl alcohol. Phases in marked 
contrast to preceding, initial relaxation, rapidly developing secondary with 
maintained plateau becoming reversible. 
9. Typical curve using 17.2 vol. per cent ethyl alcohol. Stimulating 
with modified toxic effect; note the rather prolonged initial relaxation fol- 
lowed by rapidly developing secondary with sharply descending plateau. 
TO. Typical curve using 9.1 vol. per cent ethyl alcohol. Stimulating 
with more slowly toxic effect. Gradual onset of secondary contracture 
and maintenance of plateau and reversible decline. 
11. Typical curve using 7.4 vol. per cent ethyl alcohol. Not greatly 
different from preceding. 
12. Typical curve obtained under same experimental conditions as all 
the others but in physiol-salt solution, 0.7 vol. per cent. Note the initial 
relaxation phase accom'panied by treppe at the top, the gradual onset of 
secondary contracture, and a slowly reversible decline, with maintained 
gradual inclined plateau. 
13. Characteristic curve resulting from, immersion in strong propyl 
alcohol. Primary contracture very evident with no reversal to relaxation 
whatsoever, immediate onset of secondary contracture, terminating in 
irreversible plateau. 
14. Typical curve using saturated solution of propyl alcohol. A slight 
assumption of initial relaxation, no treppe, uniform plateau almost irre- 
versible. 
15. 16, 17. Typical curves using 13.5, 5.9 and 3.7 vol. per cent propyl 
alcohol. First two maintaining almost an irreversible plateau, the last 
showing a rapid decline. 
