Page:Popular Science Monthly Volume 88.djvu/451

Rh ject through the sides by the same method of packing that is ordinarily used at the propeller shaft. The hull, or body, is hung on large steel springs, similar to those used on stock automobile bodies. These springs, as may be seen in the illustrations, are not exposed, but are contained within the hull with the rest of the mechanism, and are protected from all dust, grit and water. The sides of the boat-automobile are high enough to prevent the shipping of water, but the machine is not designed to be operated in rough weather.

The hydro-motor car rides well in the water, and is able to attain a speed of about ten miles an hour.

This hydro-motor has proved so successful that its inventor, Michael de Cosmo, of San Francisco, is designing a new model which he expects to exhibit in the near future. Several improvements suggested during the experiments with Delia," will be made soon.

HE repainting of thousands of passenger and freight cars presents a big problem for the average railroad. It also represents a large expense, which the roads are trying to cut down by increasing the durability of the paints and shortening the time that cars must be kept out of service during the process. It is the aim of practically every road to keep its cars in continual use, where-ever possible.

Very recently the Pennsylvania Railroad established a test department, for the purpose of speeding up the work of inspection and repairs and thereby reducing the loss due to idle cars. One problem that had engaged the attention of the railroad officials was that of reducing the time required for drying a car after painting. Their not been satisfactory, as they proved less durable than those requiring two days or more to dry.

This led to experiments in baking the slow-drying paints, and for that purpose experience, however, with quick-drying paints had the railroad recently constructed a mammoth baking oven at Altoona, Pa. It is large enough to accommodate cars of almost any length. With the car well inside, the doors are closed and the temperature is raised above the boiling point of water. The paint is completely dry and hard and the car ready for service in about three hours.

The saving of time by this process has been very marked. It has reduced by ninety-five per cent, the time usually required for drying cars by the old method and has cut in half the time a car is held out of service during repainting. Besides, the artifically dried paint is claimed to be much more durable than that dried in the open air.