# Page:Popular Science Monthly Volume 2.djvu/181

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PHYSIOLOGICAL POSITION OF TOBACCO.

Pulsation before smoking, 75 pulsations per minute.

Smoking 6 minutes—76, 75, 79, 79, 76, 78.

Smoking 1 minute—82. Cease smoking.

Smoking 10 minutes—81, 88, 83, 82, 84, 83, 83, 80, 82.

The rate of pulsations was maintained, but was not materially increased.

Experiment 5.

(To prove if the rapidity of smoking causes a variation in increase of pulsation.)

a. Greater volume of smoke.

Pulsation before smoking, 70½ per minute.

Smoking 6 minutes—68, 70, 71, 70, 72, 74${\displaystyle =}$70.8 average.

Smoking 6 minutes—76, 77, 86, 89, 91, 94${\displaystyle =}$85.5 average.

Smoking 4 minutes—98, 05, 96, 95${\displaystyle =}$96.0 average.

The maximum effect was thus 27½ pulsations per minute.

b. Smoking faster.

Pulsation of the last minute in the previous part of this experiment, viz., 95 per minute—smoking 3 minutes, 94, 49, 96.

c. The pipe recharged.

Smoking 5 minutes—87, 93, 96, 96, 96.

There was, therefore, a large effect upon the pulsation, but probably not more than would have occurred with ordinary smoking.

Numerous other experiments were made with tobaccos of different reputed strengths and upon different persons, and the author gave minute directions as to the proper method of making such inquiries."

The heart, then, during the act of smoking, was doing extra work; in some of the experiments this additional labor amounting to more than 50 per cent.

The effect upon the heart is not caused by direct action upon that organ, but by paralyzing the minute vessels which form the batteries of the nervous system. Thus paralyzed, they can no longer offer effectual resistance, and the heart, freed from their control, increases the rapidity of its strokes, expanding the vessels, with an apparent accession, but real waste of force.

Its effect in lowering the animal temperature is very striking. When the walls of the blood-vessels are distended with that fluid, the increase in volume decreases the rapidity of the circulation and augments the local warmth. When the walls partially collapse, the circulation becomes quicker, but the heat diminishes. The heat, in fact, is transformed into motion.

The action of nicotine upon the iris is well known, yet, while some consider it to produce dilatation, others affirm its effect to be contraction. The iris is composed of two orders of muscular tissue. The circular fibres influenced by the motor oculi, and the radiating fibres obeying the great sympathetic, perform the two functions of the iris,