The Sper­ry Gyro-Com­pass, by The Sper­ry Gyroscope Co.

Copyright, 1920

THE SPERRY GYROSCOPE COMPANY

BROOKLYN, N. Y., U. S. A.

DESIGNED, ENGRAVED

AND PRINTED BY

ROBERT L. STILLSON

COMPANY NEW YORK

THE SPERRY GYROSCOPE CO.

MAIN OFFICE AND FACTORY

MANHATTAN BRIDGE PLAZA.

BROOKLYN, N.Y.

THE SPERRY GYROSCOPE COMPANY

Boston, Mass.

60 VIRGINIA STREET

Great Lakes District

828 GUARDIAN BUILDING

Cleveland, Ohio

San Francisco, Cal.

52 DAVIS STREET

Main European Office: THE SPERRY GYROSCOPE COMPANY, Ltd., 15 Victoria Street, London, S. W. 1

—REPRESENTATIVES—

FranceHollandNorway
COMTE A. DeCHAMBURE
37, Rue Bergere
Paris
TECHNISCH BUREAU VAN LEENT
Nassaukade 17
Ryswyk
OTTO PLATOU
Skovveien 39
Christiania
ItalyJapan
GEORGES BREITTMAYER
20, Rue Taitbout
Paris
F. P. CAMPERIO
Via Bagutta 24
Milan
MITSUI & CO., LTD.
Tokyo
Sweden
F. J. DELVES
20, Rue Taitbout
Paris
GRAHAM BROS.
Stockholm
MITSUBISHI ZOSEN KAISHA, LTD.
Tokyo
(For Ship Stabilizer)
SpainDenmarkChili, Peru & Bolivia
F. WEYDMANN
Victoria 2
Madrid
C. KNUDSEN
11 Kobmagagade
Copenhagen
WESSEL DUVAL & CO.
25 Broad Street
New York

THE
SPERRY GYROSCOPE
COMPANY

Manufacturers of

GYRO-COMPASSES

GYRO SHIP STABILIZERS

GUN-FIRE CONTROL APPARATUS

NAVIGATIONAL INSTRUMENTS

NAVAL AND COMMERCIAL SEARCHLIGHTS

The ancient Egyptians built boats of rushes.

Putting the Earth to Work

HEN the earth was thrown off from the sun and commenced rotating about its own axis, there was developed a force generated by the earth’s rotation. For countless centuries this force has been at work, but no one has ever been able to harness it to serve the purposes of man. But now, through the efforts of Foucault, Hopkins, Sperry, and other noted scientists, this force has been put to work. It serves to direct a thousand ships in their courses.

Of course, this is not the only force which has been used to guide ships. Since 1297 A.D. mariners have used magnetic attraction as the force by which to guide their vessels. For centuries seafaring men sailed only in wooden ships, and were therefore satisfied with the magnetic compass. Then came steam and steel. Navigation then instead of being a hit or miss game of chance became the exact art of directing a ship by the shortest possible course in the quickest possible time.

Now that ships cost millions of dollars to build and thousands of dollars per day to operate, time has become the most essential element in navigation. The development of ships from the sailing vessel to the ocean greyhound has been one of the marvels of modern times. But the development of the magnetic compass has not kept pace with the development of the ships which rely upon it. Many of the great trans-Atlantic liners are guided by practically the same type of compass as that which Columbus used on the Santa Maria. The compass on the wooden Santa Maria pointed to magnetic north with a fair degree of accuracy, but the compass on the steel greyhounds must contend with many distractions.

For years magnetic compass designers spent their efforts to produce compensating devices that would annul the effects of all external influences, so that the magnetic compass would be free to indicate only the direction of the earth’s magnetic lines. Very little has been done to improve the compass itself—it still depends upon the attraction of the Magnetic North Pole. The Sperry Gyro-Compass differs in principle from any other compass. It is not magnetic. It derives its directive force, not from magnetic attraction, but from the earth’s rotation.

The Vikings crossed the Atlantic in open ships.

There is certainly a crying need for this new type of compass. A ship now-a-days costs millions of dollars and carries cargoes usually equal in value to that of the ship. It has been estimated that inaccuracies in navigation attending the use of the magnetic compass cause a yearly loss of ships to the value of $70,000,000. No estimate can possibly be made on the value of lives lost on these ships.

Millions of dollars are spent each year on charts, lighthouses, buoys, geodetic and hydrographic surveys, and on compilation of notices to mariners. Notwithstanding all of these, ships must ultimately depend upon their compasses for their safety and efficiency of navigation.

Inaccuracies in navigation can be eliminated by the use of a reliable compass. The Sperry Gyro-Compass puts the earth to work. It utilizes a force which is as unvarying as the law of gravity, a force that cannot be interfered with by any other influence.