General physiology; an outline of the science of life . ted toward the oesophagus. If westretch such a piece with four needles upon a cork frame (Fig. 182)and cover it with a cover-glass, we can observe the ciliary motionfor days, if the object be protected from drying, and study its rate,either directly under the microscope, or by the passage of blood-clots or particles of coal-dust laid upon it. In such a preparationit is easy to determine that the rate and energy of the motion1 Cf. Verworn (96, 2, 3). 394 GENERAL PHYSIOLOGY increase with increasing temperature. The same phenomena canbe obse
General physiology; an outline of the science of life . ted toward the oesophagus. If westretch such a piece with four needles upon a cork frame (Fig. 182)and cover it with a cover-glass, we can observe the ciliary motionfor days, if the object be protected from drying, and study its rate,either directly under the microscope, or by the passage of blood-clots or particles of coal-dust laid upon it. In such a preparationit is easy to determine that the rate and energy of the motion1 Cf. Verworn (96, 2, 3). 394 GENERAL PHYSIOLOGY increase with increasing temperature. The same phenomena canbe observed as easily and perhaps more clearly in Infusoriawith the warm stage. Rossbach, who first made such investigationsupon various Ciliata, describes how the ciliary motion suddenly in-creases in rate, so that at 25° C. the Infusoria begin to shoothere and there like arrows, and at 30°—35° C. their motionsbecome really furious. Muscle behaves analogously. If a frogs muscle be hung in a0*5 per cent, solution of common salt, the temperature of which. Fig. 182. —Oral mucous membrane of the frog stretched upon a cork frame. is rapidly increased, the muscle shortens gradually withincreasing temperature from about 28° C. on, until at about45° C. its contraction has reached its maximum. But if themuscle be dipped suddenly into a salt solution of 45° C,there appears at once a sudden contraction. The irritability ofmuscle is also increased with rising temperature. Thus, everywhere in living nature the law is met with, that withincertain limits increasing temperature acts to augment vital processes. b. The Phenomena of Depression Falling temperature produces effects opposite to those of risingtemperature. If the temperature be constantly lowered from theaverage at which an organism normally exists, it is found that thevital phenomena constantly decrease in energy, and that from acertain low degree on—which point is very different for differentorganisms and different phenomena
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