This instrument is used for studying the temperature structure in the upper 10 m of water. The instrument is in two sections; a float, which contains a spooling winch from which the sensing unit is lowered, and an indicator case, which contains the remote indicating equipment and remote control system. The two sections are connected by an electric cable and flexible shaft, supported by net floats. The indicator case is clear lucite. It contains the indicating meter and electric circuitry for temperature determination. It also contains a Veeder-Root counter, which indicates directly in centimeters the depth at which the sensing unit is located. This instrument makes it possible to read temperature to within 0.1 degrees C and to know the depth of the sensing unit to within + or -0.5 cm. It is intended to be used at sea from a skiff or tender rather than from the research vessel itself.