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When molybdenite is heated by thermal conduction or exposed to thermal radiation it exhibits hitherto undescribed thermoelectric, actinoelectric and photoelectric properties. The paper gives precise definitions of these terms. The investigations were divided into three portions under the above headings, and were conducted with molybdenite in the form of thin cleavage pieces, to which were (attached fine copper wires to form the thermojunctions. The method used was similar to that previously recorded [Abstract 1919A00337], and the sample under examination was mounted upon a sliding carriage behind a slit 0.1 mm. wide and 1 cm. long. Thus, by using another slit travelling at right angles to this, any precise spot could be investigated. Light was derived from a tungsten filament lamp. The effects were investigated by the use of both Thomson and D'Arsonval galvanometers. /b Thermoelectrical Properties/. - The first part of the paper shows that, owing to lack of homogeneity, standard thermoelectric data cannot be specified for molybdenite. Samples from various localities, as given in the data, show a range of thermoelectric power against copper from +700 microvolts, through zero thermal e.m.f., to - 1040 microvolts. /b Actinoelectrical properties/. - A new actinoelectrical phenomenon is described, consisting of an e.m.f. exhibited in spots or loci of some samples of molybdenite when exposed to thermal radiation of short wave-lengths. Spots separated by only 0.5 to 1.5 mm. will exhibit actinoelectric e.m.f.'s of different polarity. The wave-length of the thermal radiation stimulus determines whether the spectral actinoelectric effect will be photopositive or photonegative. Radiation stimuli of wave-lengths between 0.65 and 0.9mu give maximum actinoelectrical e.m.f.'s and wave-lengths greater than 1.0mu give no effect. The maximum actinoelectric response is apparently instantaneous for all wave-lengths. /b Photoelectrical properties/. - Photoelectrical effect is exhibited by the production of a change in resistance when the molybdenite crystal is subjected to an impressed potential and exposed to light. The change in resistance is photopositive or negative according to the wave-length of the stimulating source. The photoelectric reaction is produced by radiation over a range of wave-lengths from 0.3mu. to 2.0mu. The maximum photoelectric response is attained in a time which is a function of the wave-length of the exciting radiation, and is of the order of from one to several minutes. Double this time is required for recovery after exposure. Molybdenite of low resistance, low photoelectric sensitivity and high actinoelectrical sensitivity exhibits spectro-photoelectrical reaction which is apparently instantaneous for all wave-lengths. The effect of temperature, variation of intensity of exciting radiation, etc., are investigated and data given. In general, these factors have no marked effect upon the spectral actinoelectrical reaction or they are the reverse of the effect upon the spectro-photoelectric reaction. A difference of from 1.5 to 2.5 times between the maximum and minimum photoelectric effect is produced when there is a close coincidence of the spots exhibiting photoelectrical and actinoelectrical sensitivity, the photoelectric current being amplified or weakened according to the direction of the impressed potential through the crystals. From the data supplied it may be concluded that the actinoelectric phenomenon is independent of other agencies that may be acting in molybdenite.

"The mother cat had been quite upset when she first saw the blue kitten. She had looked fearfully then toward the river. For, like all cats, she had heard that a blue kitten could learn the river's song. Any kitten has a hard enough time to find a home for himself. For every kitten must find a hearth to fit his song. But a kitten who listens to the river and learns the river's song has the hardest time of all. Not only must the kitten who sings the river's song find a hearth to fit that song, but he must teach the keeper of that hearth to sing the same song. The river's song is very old. And mortals who have ears to hear and hearts to sing are fewer than few." (From The Blue Cat of Castle Town)<br /><br />This project was proof listened by Catharine Eastman, ElleyCat, and Park Chohwa.

2When the Birds Fly South

By Stanton A. Coblentz

Dan Prescott, an American adventurer, discovers the hidden valley of Sobul in a mountainous region of Afghanistan, inhabited by a strange race of winged people known as the "Ibandru". He falls in love with one of them, Yasma, and they marry in a scene of general celebration. When fall comes, however, the Ibandru abandon their valley to fly south with the birds for the winter, taking Yasma with them. The importance of Stanley Coblentz's Lost World fantasy was confirmed by its reprinting as the 23rd volume in the prestigious Newcastle Forgotten Fantasy series in 1980. - Summary by Adapted from Wikipedia