Page:Popular Science Monthly Volume 90.djvu/111

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Popular Science Monthly

��95

��A Machine Which Abuses

Boxes to Find Out How

Strong They Are

TO determine the best kind of box construction for a given purpose, a machine for testing boxes is now in operation at the Forest Prod- ucts Laboratory, at I\Iadison, Wisconsin. This machine was devised by the engineers of the United States Forest Ser- vice after consulting the American Society for Testing Materials and the National Association of Box Manu- facturers.

As more than four and a half billion feet of lumber are used in making boxes every year and as many boxes are broken in transit, with injury to their contents, it is hoped to effect a big economic saving by finding out through this machine just what are the best methods of box construc- tion.

The machine has an hexago- nal drum, the sides of which measure three and a half feet, is lined with sheet steel.

���Boxes tilled with cans of water are placed in the hexagonal drum which is then rotated. The results of falls are noted

��The drum

Pieces of scantling bolted to the bottom form the "hazards." Boxes filled with cans of water are placed in the drum. It is then rotated. The hazards carry the boxes part way up and then they fall back into the lower part of the drum. The boxes are watched carefully, and the number of falls they with- stand and the manner in which they break are care- fully registered.

As a result of these tests the way in which the boxes are nailed has been found to be ver>' important. One more nail to each side of a box gives it much greater strength. Proper nailing will allow a reduction in thi amount of lumber used. without decreasing the strength of the box. Boxes with cleated ends are found to be very strong. The quality of the lumber isfound to be less important than the manner of construction.

���The point is shoved into the device which grips it so that it is extracted with a pull

��At Last! A Device for Extracting Rusty Pen -Points

THE usual method of extracting rusted pen-points from their staffs, is to pull them out with the fingers, if it can possibly be done. Inky fingers are the least of several evils resulting from this method of procedure. Among others is the chance of cutting the flesh and adding a rub}^ color to the ink- marks made by the be- smeared fingers.

A pen-extractor screwed to the wall or desk will serve the entire office or class- room, where such pens are used, and will do its bit toward effecting the smooth and rapid carrying out of the daily routine. The pen- point is shoved as far as possible through the door or shutter of the device, which grips it automatically. With a pull on the staff the point is extracted. A receptacle is provided into which the discarded point falls.

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