Circular presenting the Morane Saulnier 222 airplane, which is a single-seat pursuit monoplane. A description of the components, design, characteristics, performance, photographs, and drawings are provided.

Circular presenting a description of the Amiot S.E.C.M. 110 C.1, which is a single-seat pursuit monoplane. Some of the design principles that the aircraft was built from are provided. A description of the design, components, dimensions, flight characteristics, and photographs are provided.

This report presents a thermodynamic basis for rating heat engines. The production of work by a heat engine rests on the operation of supplying heat, under favorable conditions, to a working fluid and then taking it away.

The Nieuport Delage 640 is a single engine commercial high-wing monoplane of all wood construction, including the fuselage and tail. It's landing gear is hinged in two parts.

Circular describing the Saunders Cutty Sark commercial seaplane, which is a high-wing monoplane flying boat. Details regarding the power unit, engines, fuel system, components, characteristics, drawings, and photographs are provided.

Circular presenting a description of the Westland IV, which is a high-wing monoplane with strut bracing, two outboard engines, a fairly large fuselage that provides comfortable cabin accommodation, and wide-track landing gear. Details of the design, flight characteristics, blueprints, and photographs are provided.

The Partridge is a tractor biplane of orthodox design. It has a single supercharged Jupiter VII engine.

The F180 was designed for reliable long distance travel in stages of 500, 1000, 1500 km, carrying loads of 2500, 2000, and 1500 kg respectively. At maximum load it can carry 20 passengers.

This report presents the results of tests conducted to determine the effect of different amounts and kinds of cowling on the performance and cylinder temperatures of a standard Wright J-5 engine. These tests were conducted in conjunction with drag and propeller tests in which the same cowlings were used. Four different cowlings were investigated varying from the one extreme of no cowling on the engine to the other extreme of the engine completely cowled and the cooling air flowing inside the cowling through an opening in the nose and out through an annular opening at the rear of the engine. Each cowling was tested at air speeds of approximately 60, 80, and 100 miles per hour.

Circular presenting a description of the Bernard 20 C.1, which is made of wood and has four main parts: a one-piece wing with a fuselage in the middle, a rear section with the tail surfaces, an engine mount, and a landing gear.

Circular presenting a description of the Blackburn Bluebird Mark IV, which is an all-metal airplane. Details are provided regarding constructional features, the cockpit, the gasoline system, and the flight characteristics.

Many treatises in regard to construction of airship sheds are lacking in data on air currents, for which reason this phase of the problem will be here thoroughly discussed in connection with the accompanying photographs of currents.

Circular describing the Potez 33, which is a military airplane that can be used for other purposes such as training pilots and as a messenger airplane due to its maneuverability and low landing speeds. A description of the controls, components, potential uses, characteristics, performance, drawings, and photographs are provided.

Circular describing the Morane-Saulnier 180 light airplane, which is a single-seat training monoplane. A description of the components, design, characteristics, theoretical performance, drawings, and photographs are provided.

Report presenting data on gold production around the world, with specific focus on the gold production the United States.

Report presenting summarized data of zinc production, both in the United States and around the world.

Report presenting information on the production of lead since 1800.

From introduction: The purpose of this paper is to present a detailed description of the methods employed and the equipment used, with the results obtained in the operation of this mine in the thick Freeport bed on the northern end of the field, near the Alleghegny-Butler county line in western Pennsylvania. It may be classed as a captive mine, as the largest portion of the product is consumed at the by-product plants of the parent company

From introduction: The production of gypsum is one of the oldest industries in Canada, and in point of gypsum output Canada ranks third among the countries of the world. Gypsum was discovered in the Maritime Provinces at a very early date, but there is no authentic record..of production until about 1822, when gypsum was mined on a small scale in Ontario. Since.then the production has grown slowly but steadily to more than a million tons. In 1928 the output was 1,205,846 short tons, valued at $3,622,007.

From introduction: acknowledgements.-The Forsyth field was examined to collect data upon which to classify the public land included in it with regard to its value as coal land. The geologic mapping was done with the plane table and telescopic alidade, and all locations were tied to land corners.

From introduction: The discovery of oil near Kevin, Mont., in March, 1922, gave prominence to the Sweetgrass arch, which is a large structural uplift somewhat similar in size and degree of folding to the Cincinnati arch. Most of the development so far attempted on this fold has been on the Kevin-Sunburst dome, a bulge upon the crest of the arch just south of the Canadian boundary. The dome covers about 16 townships, is nearly circular in outline, and has very low dips away from its highest point in all directions. Within the last five years (1923-1927) about 1,500 wells have been drilled upon it, over 880 of which are rated as productive. Since May, 1925, the field has stood second in production in the Rocky Mountain States being exceeded only by Salt Creek.

Report on the comparative gravities of oil extracted from different regions of the United States.

Report about ocher or ochery earth, "a natural mineral pigment composed largely of clay permeated with hydrated iron (ferric oxide)" (p. 2). It includes information about the uses of choer, substitutes, artificial ocher, mining and local deposits, import and export of ocher, and related information.

Report of the annual conference on weights and measures, hosted by the U.S. National Bureau of Standards in Washington D.C. It includes conference proceedings, a list of attendees, information about committees and officers, and other reports or commentaries discussed at the meetings.