Page:Popular Science Monthly Volume 90.djvu/620

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��Popular Science Monthly

��Drawing Outlines for Forming Scrolls on Ionic Capitals

THE secret of the beautiful curves of Ionic architecture is said to be trace- able to a seashell.

The skillful artist fastened a string to the stylus and then wound it about the shell from the top to the bottom. The shell used was in the form of a top with a spiral groove running down its side. The point was placed in the center of the proposed scroll and the mark was made with the stylus, pulling at the same time on the string, which gradually unwound from the shell and released an ever lengthening radius for the stylus to work in. This produced a

����The method employed in forming Ionic scroll- curves with the aid of a periwinkle seashell

scroll with an accurate and beautiful curve. Various types of scrolls were produced, according to the size and shape of the shell. — Harold V. Walsh.

��Marking Date of Repairs on Auto- mobile Tires

HOW can I mark my repair work for future identification? This is an oft- repeated question that comes from repair- men who have tried many systems. Here is a scheme that has been found very effi- cient: A tin strip, J^ in. wide and just long enough to make the necessary figures, is stamped by a machine that punches the

��letters in backwards. This strip is placed against the uncured rubber, with the em- bossed side of the tin turned out. When the job is cured the tin strip is peeled ofif and the rubber is found to have been forced into the little grooves of the letters, forming a perfect mark. The average repairman might find such a punching machine a little too expensive for his requirements, but by providing himself with a set of letter punches, which as a general rule are inex- pensive, with a hammer he could make a few of his own strips.

Probably the best place to mark a tire repair job is close to the bead. The re- pairman might save labor if he punched his initials on a separate strip, for then strips with just the dates could be made up each morning as needed.

��Re- Shellacking a Cork- Float on an Automobile Engine

WHEN re-shellacking the cork-float of a carbureter it should be first carefully sandpapered to remove all particles of the old shellac. If this caution is not observed, additional weight will be added to the float which will necessitate a readjustment of the carbureter. This may seem unimpor- tant, but it will result in trouble when starting the engine. A very slight change in the weight will cause considerable differ- ence in the amount of gasoline admitted and unless the reason is known it is hard to locate the trouble.

��Tea Kettle with Whistle in Spout for a Signal

THIS kettle has no detachable top but it is provided with a generous spout through which it is filled and emptied. Attached to the handle by a chain is a small signal whistle which is slipped into the spout to announce the boiling point. There is possi- bility of a small fuel economy due to the scarc- ity of vents and

���Tea kettle which is filled and emptied through spout

��the undoubted advantageof having no cover to slip ofif during the pouring operation.

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