Describes how to plan and build small concrete structures on the farm.

Describes various potato-tuber diseases, as well as the various methods of control of these diseases.

Describes the characteristics and life history of the common cabbage worm, the damage it can cause, and methods of control.

Describes the characteristics and life cycle of the potato leafhopper, and methods for control.

"This report is the first of a series of four on propeller design and contains a description of the blade elements or modified Drzewiecke theory as used in the Bureau of Aeronautics, U.S. Navy Department. Blade interference corrections are used which were taken from R.& M. NO. 639 of the British Advisory Committee for Aeronautics. The airfoil characteristics used were obtained from tests of model propellers, not from tests of model wings" (p. 1).

This report is the second of a series of four on propeller design, and describes the method used to extend the data obtained from tests on a family of thirteen model propellers to include all propellers of the same form likely to be met in practice. This necessitates the development of a method of propeller analysis which when used to calculate the powers and efficiencies gives results which check the tests throughout their range.

"This report, the third of a series of four, describes a simple system for designing propellers of a standard form. In this report, the system is based on tests of a family of model propellers of standard Navy form, the data from which have been extended by means of calculations to cover the complete range likely to be found in practice. However, it can be worked out for any family having propellers of one general form" (p. 1).

Circular presenting a description of the Arado Ar. S.I., which is a wireless biplane that is both physically attractive and highly performing. A description of the components, controls, construction, characteristics, flying qualities, drawings, and photographs are provided.

Circular describing the all-metal Junkers airplane, specifically the F 13 type. The primary characteristics of the airplanes are the thick cantilever Junkers wing without stay-wires and the all-metal construction. A description of the design, flight characteristics, and some photographs are provided.

It has long been thought that metal construction of airplanes would involve an increase in weight as compared with wood construction. Recent experience has shown that such is not the case. This report describes the materials used, treatment of, and characteristics of metal airplane construction.

A method is presented for photographing the flow of fluids with a kinetograph.

While little has been accomplished in obtaining an abundant supply of light oils from coal and heavy oils, progress has been made on engine design to make use of the heavier oils. Progress has been made in two different directions which are outlined in this paper: the group of engines with medium and high-pressure carburetion in the cylinder; and the group of engines with low-pressure carburetion of the heavy oils before reaching the cylinder.

Technical paper issued by the Bureau of Standards over studies conducted on the endurance of tires. 230 tires of 36 different brands were tested during the studies. The results of the studies are presented and discussed. This paper includes tables, and photographs.

This report is an evaluation of the experiments on the use of heavy oils in explosion engines. A method for determining the heat of vaporization of these heavy oils is presented.

Circular describing the Vickers "Vendace", which is a land or sea training tractor biplane. Details of the design, wings, construction, control surfaces, fuselage, fabric, cockpits, fuel supply, landing gear, characteristics, and drawings are provided.

Circular presenting a description of the Short "Mussel" S.7, which is designed for use as a light training airplane of robust and simple construction. Information regarding the design, blueprints, and photographs are provided.