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At the tip of the staff on the Royal Exchange in London, is a huge grasshopper figure which serves as a weather vane and honors Sir Thomas Gresham, who founded the institution during the reign of Queen Elizabeth. Once a year, the vane is given a thorough cleaning by a steeplejack.

 

Parquetry flooring can be installed at about the same cost as strips, it is said, with specially prepared units, joined together with tongues and grooves on all sides. The blocks are made in two sizes, one eighteen inches and the other thirteen and one-half inches square. They are composed of carefully matched smaller pieces ready for laying, and it is claimed no special requirements are needed for the subfloor, which may be the same as that prepared for the strip flooring.

 

With a camera that can take 20,000 pictures a second, movies of air currents have been prepared for reference study in aviation. Details of breezes moving at fifty miles an hour, are revealed so clearly that the eye can easily follow the movements around various obstacles. The flight of a pistol bullet through an electric-light bulb looked like the slow bending and final disintegration of the glass. Currents of air from a windmill and the passage of the air around an airplane wing were also shown. The film was recently exhibited in New York, after being prepared in Japan with the "super slow-motion" picture camera developed there. The instrument is the outgrowth of research by German scholars and craftsmen. It has two parallel disks, one with a large number of small mirrors which reflect the image obtained through the lens of the other disk, which holds the films.

 

By anchoring the landing lights on his aviation field to flexible cable supports that bend over without breaking when struck, a Texas manager has found a way to preserve the lamps and prevent damage to airplanes. The plan was adopted after several accidents had occurred, when ships struck the rigid standards.



