CONSTANT TEMPERATURE CIRCULATORS FOR MAINTAINING LIQUID BATHS AND CIRCULATING LIQUIDS AT A SUBSTANTIALLY CONSTANT TEMPERATURE, WARBURG APPARATUSES I. E. APPARATUSES FOR PRECISE MICROGAS ANALYSIS, ELECTRO KYMOGRAPHS, ELECTRIC RECORDING DEVICES FOR RECORDING PH TEMPERATURE AND PRESSURE ELECTRONICALLY, ARTERIAL BLOOD FLOW METERS, INFUSOMETERS, PRECISION LABORATORY STANDS, ELECTROPHORESIS APPARATUSES, SPECTROPHOTOMETERS, COLORIMETERS, VISCOSIMETERS, POLARIMETERS, REFRACTOMETERS, MANOMETERS, THERMOMETERS, PIPETTES, REACTION FLASKS, SYRINGES, AND LABORATORY GLASSWARE