Page:Popular Science Monthly Volume 92.djvu/571

 Popular Science MontJily

The Forest Skyscrapers of Australia

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��^HE tallest of California's "big trees" is 325 feet in height, but among the great gum trees of Australia many specimens are more than 400 feet in height, and one, which was felled in southeast Australia, measured 471 feet — the tallest tree on record. Gum trees grow very rapidly.

��A Motorcycle as a Vibra- tionless Tripod

BREATHES there the pho- tographer who has not at some time or other "lost his re- ligion" because the wind has shaken his tripod and spoiled a plate? John Edwin Hodd, a Los Angeles press photographer who uses a motorcycle for getting about, has over- come this difficulty so far as exterior views are concerned, by the use of a uni- versal jointed kodak fastening attached to the handle bar of his machine.

The motorcycle is placed on its stand at a convenient dis- tance from the ob- ject to be photo- graphed, and by the use of the universal joint the camera is pointed in any direc- tion or at any angle. Attaching or detach- ing the instrument is but the work of an instant.

Because of the great weight of the motorcycle the camera is held per- fectly rigid even in a strong wind. Clear- cut, perfect pictures are the result, and the necessity of car- rying a tripod is avoided. The attach- ment is not in the way.

���French Official Photo

Sirens on top of the Equitable Life building in Paris give warning when German raiders are approaching

Sirens Give Warning of the Ap- proach of Raiders

IN the French cities warning of German air raiders is given by sirens of different

construction, some

electric, others work- ed by compressed air or steam. The sound of these sirens is so powerful and pene- trating that it can be heard for miles even under unfavor- able conditions. Lookouts are main- tained at elevated points and day and night close watch is kept upon the hori- zon line in the di- rection toward the enemy.

Paris itself, how- ever, has been almost immune from aerial attack. To cross the anti-aircraft guns and to elude the patrol- ling airplanes is prac- tically an impossibil- ity since the retire- ment of the enemy.

���This press photographer uses his motor- cycle as a firm, portable camera tripod

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