Abstract. Measurements were made to determine the effect of thermal cycling on heat transfer from slug to jack using a slug with a sand blasted surface. The value of the transfer coefficient h decreased from initial values ranging from 10 to [formula], to values and [formula] after 1700 cycles, and to a range of 0.15 to 0.45 [formula] after 3200 cycles. Comparisons are made with the results found for slugs with different surfaces.

Report presenting the drag of a series of complete airplane-like configurations and their components at transonic velocities using the free-fall method. The configuration tested in this report has a 45 degree sweptback wing of aspect ratio 4.1 mounted forward of the maximum diameter of a 10-inch-diameter body of fineness ratio 12 equipped with stabilizing tail fins. Results are presented as curves showing the variation of drag coefficient with Mach number for the complete configuration and for each component.

Memorandum presenting the results of measurements of gust and draft velocities within thunderstorms at a selected air field over a 5-day period. They are also compared to previous flights.

This report discusses the poisoning effectiveness and uniformity of the first production batch of 33 myrnalloy slugs which was tested in the 305 Test Pile on February 26, 1946, prior to charging into the D Pile in accordance with Production Test No. 105-49-P, supplement A.

"This work is a continuation of an investigation begun in January, 1945, on a laboratory study of various methods for the chlorination of TO3. The work carried out this month deals entirely with gas phase chlorination, the liquid phase chlorination of TO3 having been turned over to Miss Hubbard. Gas phase chlorination of TO3 by means of CCl4, S2Cl2, SOCl2, SO2Cl2, and Cl2 have been carried out under varying conditions in the several different types of reactors."

Description of a velocity analyzer (with diagrams) is given. It is a device for measuring the velocities of charged particles which comprises pairs of spaced electrodes, a collector for charged particles, and means for propelling charged particles in a direction so as to pass between the pairs of electrodes. The pairs of electrodes and the collector are so arranged to permit passage of the charged particles between them to the collector plate. Means are provided for applying an alternating substantially square wave potential of known frequency to the pairs of electrodes so that adjacent pairs are opposite in phase and so that one half-cycle of the wave appears as zero potential between the pairs of electrodes.

Abstract: "Gravitational observations were made of the pre-Cambrian Coal Creek serpentine mass in Blanco and Gillespie Counties, Texas, the geology of which had been mapped previously. The observed gravitational anomalies indicate roughly the depth of the serpentine mass below which it may possibly grade into its parent peridotitic rock. Probable correlation between the gravitational map and the other geologic features of the area is indicated" (p. 151).