Submarine Illumination in Photometric Units

Limnological Conditions in Ice‐Covered Lakes, Especially as Related to Winter‐Kill of Fish

“…It was found, in agreement with the statement of Utterback & Wilson (1940), that the temperature correction is greater at higher illumination levels. The' temperature correction was ascertai ned by calibration at several temperatures.…”

“…The' temperature correction was ascertai ned by calibration at several temperatures. It was found, in agreement with the statement of Utterback & Wilson (1940), that the temperature correction is greater at higher illumination levels.…”

“…Many different designs have been em-ployed (Ellis, 1934, Pearsall & Ullyott 1933, Burr & Burr 1934, Utterback & Wilson 1940 H consists of a suitably housed receiver, using two Weston "Photronic" cells, and connected by a waterproof cable to a very sensitive multiple-range galvanometer. In recent years this type of photometer has come into rather common use, pHticularly in oceanography.…”

“…In recent years this type of photometer has come into rather common use, pHticularly in oceanography. Many different designs have been em-ployed (Ellis, 1934, Pearsall & Ullyott 1933, Burr & Burr 1934, Utterback & Wilson 1940 H consists of a suitably housed receiver, using two Weston "Photronic" cells, and connected by a waterproof cable to a very sensitive multiple-range galvanometer. The brass housing case of the receiver can be fitted with a detachable pipe handle, enabling it to be thrust under the ice to a distance of about two feet from the edge of the hole which must be cut into the ice.…”