Metrograph

Metrographs have been devised for counting the revolutions and speed of locomotive wheels.

Now, equipment is available today where you can use teletype, punch cards, use a metrograph machine, or a thousand ways.

Represented by R.W. Sparling, and C. F. Sherwood, exhibited the Sparling line of main line meters and metrograph recording instruments.

The automatic records of the sunshine recorder, the anemometer and the wind vane, are registered on one instrument, which is called a metrograph or improved triple register.

The metrograph temperature sensor and the two mercury thermometers were backed up by temperature readings from nickel iron resistance thermometers and reported temperature readings from Buckley Air National Guard Base Weather Station.

The government's contribution to the radiosonde dates back to the "airborne metrograph" of the 1920's. This was a mechanical device that recorded temperature, humidity, and pressure.

Since the 1930s, the government would use radio metrographs to monitor the weather.

With the metrograph, the hologram is fixed and the point of light can be moved in the three orthogonal directions.