BECKMAN

[ BATTERY POWER REGULATORS FOR MAINTAINING CONSTANT BATTERY CHARGE DURING SPECTROPHOTOMETRIC OPERATIONS; ] POWER SUPPLY ATTACHMENTS FOR ENERGIZING ULTRAVIOLET SOURCES USED WITH SPECTROPHOTOMETERS; [ MULTIPLE ELECTRODE SWITCHES FOR CONNECTING A PLURALITY OF ELECTRODE ASSEMBLIES TO A SINGLE PH METER; ] ELECTRO-CHEMICAL ELECTRODES- NAMELY, ELECTRODES OF THE GLASS AND METALLIC TYPE AND REFERENCE ELECTODES, FOR USE WITH PH MEASURING AND CONTROL EQUIPMENT; ELECTRODE ASSEMBLIES POSITIONING SUCH ELECTRODES FOR IMMERSION OR FLOW-SAMPLE USE [ ; AND VARIABLE ELECTRICAL RESISTORS AND POTENTIOMETERS OF THE SINGLE TURN AND MULTI-TURN TYPES ]