Temp­er­a­ture changes do not in­flu­ence the Sper­ry Gy­ro-Com­pass.

No mat­ter what the con­di­tions are that change the mag­net­ic char­ac­ter­is­tics of the stack, ship or cargo, they can­not af­fect the Gy­ro-Com­pass, as it has noth­ing what­ev­er to do with mag­ne­tism.

Fulton’s Clermont ushered in the age of steam.

Influences Due to Roll and Pitch of the Ship

The Magnetic Compass

Another error, called heel­ing error, is caused by the change in the dis­pos­i­tion of the material of the ship with ref­er­ence to the com­pass. It is brought about when the ship rolls. For example, a ship heading on a northerly course would, if rolled to port, place all magnetic material of the ship to the east­ward of the compass. This pulls the north end of the com­pass to the east­ward. The action and effect would be just opposite to this on a roll to the star­board. The result is that the needle is caused to oscil­late in either direc­tion. The helms­man in his attempt to keep “on” will cause the ship to traverse a sinuous course.

The card and needle of the mag­netic compass are placed in a bowl filled with a liquid. The purpose in so doing is to make the action of the card some­what slug­gish, so that it will not follow very slight magnetic dis­trac­tions or ship move­ments. Every time the course of the ship is changed the slug­gish action, due to adhesion between the bowl, liquid and card, pulls the com­pass off the mer­i­di­an. Of­ficial test has shown that from three to four minutes are re­quired for the com­pass to over­come this “lag.” The “lag” is some­what less in the dry card compass.

The Sperry Gyro-Compass