Isotopes of francium with 126 or fewer neutrons have been looked for in bombardments of Th{sup 232} with 350 Mev protons from the 184-inch cyclotron. Fr{sup 212} with an apparent half-life of 19.3 minutes for branching decay by alpha emission (44%) to At{sup 208} and by orbital electron capture (56%) to Em{sup 212} has been found. Em{sup 212} is shown to be a 23-minute alpha-emitter. At{sup 208} decays primarily (99.5%) by orbital electron capture to Po{sup 208}, but shows 0.5% alpha-branching. The francium and emanation isotopes have alpha half-lives completely out of line with the predictions based on the previously known isotopes of these elements. Their high alpha stability is believed to be due to a closed shell of 126 neutrons in analogy to the behavior of elements 83-85. The non-existence of long-lived francium in nature is discussed in the terms of this and other recent work on francium isotopes.

Abstract: "The sensitivity to fast neutrons of a CP Meter ionization chamber of the type used for health physics beta and gamma survey measurements has been investigated."

The following report describes polarographic methods that determine saturated aliphatic carbonyl compounds.

This report summarizes the radioactive contamination measured at the Hanford Works and vicinity for the quarter July, August, and September 1948. Topics discussed are: meteorology; airborne contamination and contamination of the Columbia River; vegetation; drinking water; and in Hanford Wastes.

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Price Daniel, regarding a legal question submitted for clarification: Validity of an optional county road law election order without the petition prescribed by law.

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Price Daniel, regarding a legal question submitted for clarification: Several questions concerning the organization of the 118th Judicial District.

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Price Daniel, regarding a legal question submitted for clarification: Taxation of territory formerly comprising common school district, annexed after January 1, during the year of annexation and related questions.

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Price Daniel, regarding a legal question submitted for clarification: Interpretation of H.B. 370 giving the Board of Control authority over the tenure of superintendents of two State Schools in relation to H.B. 1, which transfers these schools to a new institutional Board.

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Price Daniel, regarding a legal question submitted for clarification: Investment of Permanent School Fund in bonds issued by Veterans' Land Board and necessity of advertisement for competitive bidding.

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Price Daniel, regarding a legal question submitted for clarification: The effect of a tax judgment upon other prior delinquent taxes which were not included in the petition or judgment, where no tax sale has been made.

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Report presenting the results of an experimental investigation to determine the downwash in the region of the trailing vortex behind a trapezoidal-wing tip in a supersonic stream. Results regarding the downwash at spanwise stations, downwash at chordwise stations, and wake survey are provided.

Report presenting an investigation of a model of a tailless airplane in a high speed tunnel at a range of Mach numbers. Results are compared to those obtained from a sting-mounted model tested in the same tunnel and a semispan model tested with the wing-flow method. Information regarding basic aerodynamic characteristics, spoiler controls, lift characteristics, drag characteristics, pitching moment at zero lift, and stability and control is provided.

Report presenting a low-speed investigation to determine the effectiveness of a conventional aileron and various spanwise spoiler arrangements on a 42 degree sweptback wing. The rolling-moment characteristics of the aileron and the spoilers, as well as the aileron hinge-moment, normal-force, and balance-chamber pressure characteristics were determined for a plain wing and a wing equipped with several high-lift and stall-control devices.

Memorandum presenting a bibliography of unclassified aircraft fire literature consisting of reports from a 20-year period ending January 1, 1949. The reports are separated into the following categories: aircraft fire accidents and statistics, combustibles, ignition sources, fire protection, fire prevention, fire resistance of materials, fire detecting, fire extinguishing, and passenger protection or rescue.

Heat-transfer data from supersonic wind-tunnel tests of a heated 20 degree cone are compared with theoretical results obtained by the method for determining the convective heat transfer in laminar boundary layers in a compressible fluid developed by Hantzche and Wendt and with the method presented in NACA TN No. 1300. The experimental data are also compared with the results obtained by Eber at the Kochel Laboratory in Germany and it is found that Eber's results correspond to those obtained with a turbulent boundary layer on the cone. The results provide a qualitative verification of the effect of heat transfer on laminar boundary-layer stability that has been predicted theoretically by Lees in NACA TN No. 1360.

Report presenting an investigation of the damping-in-roll characteristics of a 35 degree sweptback wing, with and without vertical fins, through a range of Mach numbers in the high speed 7- by 10-foot tunnel utilizing a free-to-roll technique. The damping-in-roll coefficient increased in magnitude with Mach number in the manner indicated by theory and generally was found to increase in magnitude with angle of attack over the range tested.

Report presenting an analysis of the dynamic-lateral-stability characteristics of the Bell X-2 airplane as affected by variations in mass, aerodynamic, and dimensional parameters by means of calculations of the period and rate of damping of the lateral oscillation. Results regarding the airplane with flaps and gear retracted, airplane with flaps and gear lowered, and effects of assumed modifications to the airplane are provided.

Report presenting an investigation of a family of turbine-rotor-blade designs based on one-dimensional-flow theory and incorporating systematic changes in design variables. They were designed for 40-percent reaction and a total-to-static pressure ratio of 4.00 based on the assumption of constant static pressure along the radius and one-dimensional-flow theory for the design of the rotor-blade passages.

This report provides a discussion of technical activities at the Hanford Works as of May 10, 1949.

This report details events of importance reported by the Hanford Operations Office for the week ending June 8, 1949.

The following report discusses the building design and development of the reactor building, Building 1105, for Argonne National Laboratory, that is meant to house the reactor.

Report discussing progress made by the National Research Corporation in developing preparation of ductile zirconium for the month of October, 1949.

Report discussing progress made by the National Research Corporation in developing preparation methods for ductile zirconium for the month of July, 1949.