From Introduction: "For purpose of procuring data that could be using in estimating the value of the briquetting process as applied to American fuels, the United States Geological Survey, in cooperation with other interests, began in 1904, at the Louisiana Purchase Exposition, certain experiments involving the production and use of bituminous-coal briquets."

From Introduction: "Because the limited time available would not permit a careful inspection, much less a detailed study of all the plants visited, the writer has not aimed in this bulletin to present a comprehensive review of producer-gas power-plant development in Europe, or even to give such conclusions as might be drawn from what he saw, but has simply described some interesting features of European practice that attract the attention of even a casual observer."

Postcard of a German fire station, with the firemen in front of it in three auto fire engines. A single fireman with a bike is standing to the left of the vehicles.

Postcard of three scenes in Berlin, Germany. The left and right images feature a rooms which each have a glass display and a wall of switches. The center image features a man using a street telephone at the base of a light post.

Postcard of a gated, multistory fire station in Germany. The gated area consists of three connected brick buildings, with the opening facing the camera. The main building features garages at its base and a clock at the center of its roof. The back of the photograph has a handwritten message from its sender to its recipient.