Читать книгу Rules and Practice for Adjusting Watches - Walter J. Kleinlein - Страница 19

Fig. 2 shows a box specially made for testing watches in cold. It is constructed of wood and stands about twenty-four inches high without the legs and about eighteen inches square.

A double partition packed with about one inch of sawdust will be most reliable.

The upper half of the box should contain a watertight zinc tank for holding cracked ice and about an inch of space should be left above for circulation of the air.

The chamber for receiving the watches may be about six inches square and supported by a crosspiece and attachment to the front. It should be covered above to prevent particles of ice from falling on the watches which are to be placed on the floor or on a shelf of the chamber, but the sides may be left partly open to improve the circulation of cold air. The door may also be filled with sawdust but does not require glass as the moisture would prevent observation of the thermometer which should be inside for checking up the temperature when the door is opened.

Fig. 2

The bottom of the tank should be slightly higher on one side than on the other, with a one-half inch drain pipe fitted to the low side. The inlet end of the pipe should be covered with a fine screen to prevent dirt from accumulating in the pipe and the outlet may be either at the extreme bottom or on one of the sides as shown in the cut. The upper part or cover of box should be made so that it can be easily removed for filling and cleaning the tank.