6. Apparatus
6.1 Test Tubes - Standard test tubes, 25 mm (1 in.) in outside diameter and 150 mm (6 in.) long. The test tubes shall be supplied with corks grooved at the sides to permit air circulation and bored in the exact center to receive the thermometer.
6.2 Bath - A transparent container of not less than 1500-mL capacity, that will permit the immersion of the test tubes to a depth of at least 100 mm and still leave a depth of 15 mm of water below the bottoms of the test tubes.
6.3 Thermometer, having a range as shown below and conforming to the requirements as prescribed in Specification E 1 or in specifications for IP Standard Thermometers:
6.4 Bath Thermometer, any suitable type, accurate to 0.5°C (1°F) throughout the required range.