As a result of several months of research and experiment, the first successful radio-meteorgraph was launched from Blue Hill Observatory on Tuesday; December 10. Followed by radios at Cruft Laboratory and at the Observatory, the instrument attained a height of ten miles and a distance of about 65 miles when the battery failed after more than two hours.

Former meteorographs have carried a clock or propellor to operate the instrument, as was recently described in the CRIMSON. The difficulty lay in making a clock cheap enough to be lost after every ascension and in finding an efficient propellor. This instrument carries, however, simply a screw thread whose grooves are filled with an insulating material. On this bears a contact attached to an evacuated box such as is used in an ordinary aneroid barometer. Every time the contact crosses a thread, a corresponding interruption occurs in the radio signal. This signal was received on a rotating drum. The distance between the interruptions and the number of them tells the speed of ascent and the height.

Two Streamlined Balloons

Two balloons of a new streamlined type were used to carry the instrument. Five feet high and four feet in diameter, they weigh only seven ounces, less than the conventional spherical pilot balloon.

A radio-meteorograph operated by a clock has been sent up frequently in a Weather Bureau airplane from East Boston airport since last April. Although flights were discontinued for a time because of two crashes in foggy weather, they have been recently resumed. A clear and immediate record of conditions as high as the plane goes is now received at Blue Hill.