Respirometer

Apparatus for measuring rates of absorption or evolution of gases from organisms.
Comprises two stoppered boiling tubes with wire baskets to support organisms. Each boiling tube is connected to simple manometer tube via three-way tap. The manometer tube is mounted on scale to measure the position and movement of the liquid level as gas is evolved or absorbed.
The organism of interest is placed in the basket of one of the tubes, which also has some potassium hydroxide solution to absorb carbon dioxide. The other tube acts as thermobarometer, to counteract changes in temperature. Full instructions are included.