Description: Segment 1 The intertitles give instructions on how to use the Spirometer, and it is connected to the test subject, a male. The clock is started, and the Spirometer traces the amount of air breathed. Breathing is timed for two minutes. The intertitles give instructions on how to calibrate the Spirometer. Time start: 00:00:00:00 Time end: 00:05:20:12 Length: 00:05:20:12 Segment 2 The intertitles continue to give instructions on how to use the Spirometer. The 'Douglas bag' method is introduced. The subject breathes into a tap attached to the bag. The bag is shown being prepared for use. Time start: 00:05:20:12 Time end: 00:10:36:02 Length: 00:05:15:15 Segment 3 Two tests are carried out using the Douglas bag measuring the air breathed for three minutes during rest and during exercise. The experiment to measure respiration at rest is shown. The test is repeated for basal metabolism (the subject avoids food and exercise beforehand). Time start: 00:10:36:02 Time end: 00:16:19:13 Length: 00:05:43:11