A Coupled Photometer and Respirometer

A Manometric Respirometer for Snails

IN the course of an investigation into the physiology of the edible snail {Helix pomatia L.), it became necessary to measure the respiration individually of large numbers of animals. A system in which CO,-free air was passed over the animals and then through baryta was tried but rejected because the snails apparently dislike currents of air, tending to withdraw into their shells. Analysis of ga...

Automatically Recording Respirometer.

Recently, several different types of devices have been developed which automatically record oxygen consumption of biological cultures. This article describes one of these devices and discusses its application.

Evaluation of a respirometer for neonates.

The adult (Wright) respirometer has been redesigned for neonates. A calibrated Krogh spirometer has been used to check the accuracy and a regression relationship derived over a range of minute volumes 0.4-2.8 l./min. The added resistance of 29 cm H,O/ l./sec lowered minute volume according to a second regression line which was also experimentally derived. Combining the two regressions allows tr...

The accuracy of the respirometer and ventigrator.

The respirometer under-reads at low flow rates and over-reads at high flow rates, but during anaesthesia, the respiratory waveform and the nature of the respired gas combine' to minimize the low error which would otherwise result from hypoventilation. Over-reading is to be expected during hyperventilation of the anaesthetized patient. The error will always exaggerate a departure from normality....

A lithium internal-standard flame photometer.