Your Keel.

The Water Under

Useful Device for Mariners.

THE desirability of discovering an ap paratus which will show the depth of water under a ship’s keel has been felt by mariners from time immemorial.

Sounding devices in the past have all depended mainly upon rough-and-ready measurements.

Amalgamated Wireless (Australasia) Limited has now placed on the market an instrument known as the echometer sounding device, which measures the depth of the water by the use of super sonic waves. Any depth of water be tween two fathoms and 360 fathoms can be measured instantly, regardless of the speed of the vessel or of weather con ditions, and no matter how quickly the ocean bed may vary.

The echometer is fitted to the bottom of the ship, and when brought into ac tion it transmits to the bed of the sea a signal which is reflected back and re ceived. The time occupied in the de spatch and return of the signal is regis tered, and this registration in turn in dicates the distance travelled, by which means the instrument indicates the exact depth of the water. The first ships in Australasian waters to be equipped with the apparatus are the motor ships “Wan ganella” and “Rangatira”.

It should be a device of much value to navigators in the treacherous waters of the tropical Pacific.