7. The men on shore will then pull the hawser taut, and by means of the whip line will haul off to the ship a sling, cot, or life-buoy, into which the person to be hauled ashore is to get and be made fast. When he is in, and secure, one of the crew must be separated from the rest, and again signal to the shore, as directed in Art. 1 above. The people on shore will then haul the person in the sling to the shore; and when he is landed, will haul back the empty sling to the ship for others. This operation will be repeated until all persons are hauled ashore from the wrecked vessel.

8. It may sometimes happen that the state of the weather and the condition of the ship will not admit a hawser being set up; in such cases a sling or lifebuoy will be hauled off instead, and the shipwrecked persons will be hauled through the surf, instead of along a hawser.

Masters and crews of stranded vessels should bear in mind that success in landing them in a great measure depends upon their coolness, and attention to the rules here laid down; and that by attending to them, many lives are annually saved by the Mortar and Rocket Apparatus on the coasts of the United Kingdom.

The system of signalling must be strictly adhered to; and all women, children, passengers, and helpless persons should be landed before the crew of the ship.

THE LAW OF STORMS

AND ITS PRACTICAL APPLICATION TO NAVIGATION.

[The first part of the following notice of the Law of Storms appeared, almost as now reprinted, in the early editions of this work: it is valuable as giving the most succinct account we have of the labours of our countryman, Colonel (afterwards General) Sir William Reid, in a field of observation which was entirely new forty years ago. Recent research has only modified early views of the subject, but, from a practical point, many (perhaps most) of the rules and cautions as to handling a ship in a hurricane are as valuable to-day as they were when first enunciated by Colonel Reid.)

One of the most encouraging circumstances connected with the progress of science is the practical nature of its results. In former ages, science was studied more for the intellectual pleasure which it afforded to its professors than for the sake of benefiting mankind; and yet such is the inestimable value of every truth which has been fairly established, that it remains immortal through all ages, and can be applied to practical purposes when civilisation has sufficiently advanced to enable men to appreciate its value. Who could have supposed that the properties of the conic sections discovered by the Greek Geometers would have been of infinite service in modern times in renovating the science of Astronomy and perfecting the art of Navigation ?—so that, as Condorcet well remarks, "the sailor who has been preserved from shipwreck by an accurate observation of the longitude, owes his life to a theory conceived two thousand years ago, by men

nius who had in view only simple geometrical

speculations." And who, in our own day, could have supposed that a careful study of the motions of the wind during a hurricane would have ended in ascertaining the law which regulates its movements, thereby affording to the navigator a set of practical rules for guiding his ship out of the storm, and thus escaping the horrors of the tempest, and even of shipwreck ?

It was commonly supposed that a gale of wind or a hurricane was sufficiently described when it was defined to be a wind moving in a straight course at the rate of 40 to 100 miles an hour.

The first observer who seems to have called in question this definition was Dr. Franklin. He had been prevented from observing an eclipse of the moon at Philadelphia by one of the north-east storms so common on the coast of America, and he was surprised to hear that the eclipse had been seen at Boston, although that town lay to the north-east of Philadelphia. On further inquiry he ascertained that the same north-east storm had not reached Boston until some hours after it had raged at Philadelphia, and that although the wind blew from the north-east, yet the progress of the storm was from the south-west. Franklin did not live to investigate the subject, but in 1801, Colonel Capper, of the East India Company's service, in a work on "Winds and Monsoons," gives some precise information on the nature of great storms. By a careful study of the phenomena of the great storms which swept over Pondicherry and Madras in 1760 and 1773, he arrived at the conclusion that hurricanes arc gigantic whirlwinds of a diameter not exceeding 120 miles; that they have sometimes a progressive motion, and that ships might escape from their influence by taking advantage of the land wind. He also thought it possible to ascertain the position of a ship in a whirl

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the

wind, by noting the force and changes of the wind, so as to enable the vessel to withstand its fury and escape from its vortex; for, "if the changes are sudden, and wind violent, in all probability the ship must be near the centre of the vortex of the whirlwind; whereas, if the wind blow a great length of time from the same point, and the changes are gradual, it may be reasonably supposed the ship is near the extremity of it." About the year 1831, Mr. W. C. Redfield, of New York, was by an independent series of observations led to a similar conclusion; namely, that the hurricanes of the West Indies, like those of the East, are great whirlwinds; that the whole of the revolving mass of air advances with a progressive motion from southwest to north-east; and hence he concluded that the direction of the wind at a particular place formed no part of the essential character of the storm, but that it was in all cases compounded of the whirling and progressive velocities of the storm. Mr. Redfield arrived at these conclusions by a careful study of the hurricanes of September, 1821, and August, 1830, and, having collated the accounts of the latter storm from more than seventy different localities, he laid it down on a chart, thus tracing it in a tangible form along the Atlantic coast.

This hurricane, after passing close by the Windward Islands, visited St. Thomas, one of the Virgin Islands, at midnight on the 12th of August, 1830; was near Turk Island on the 13th; at the Bahamas on the 14th; on the gulf and coast of Florida on the 15th; along the coast of Georgia and the Carolinas on the 16th; off Virginia, Maryland, New Jersey, and New York, on the 17th; off George Bank and Cape Sable on the 18th and over the Porpoise and Newfoundland Banks on the 19th; terminating to the south of the

;

island of St. Pierre, in long. 57° W., and lat. 43° N. It performed this long journey of more than 3,000 miles in about seven days, at the average rate of about 18 miles per hour.* And the whirling body of air, thus advancing upon its central axis, was from 150 to 200 miles in diameter, within which the hurricane was severely felt; but a track of from 500 to 600 miles in width was more or less influenced by its action. The duration of the most violent portion of the storm, at the several points over which it passed, was from seven to twelve hours, and the rate of its progress from the island of St. Thomas to its termination beyond the. coast of Nova Scotia varied from 15 to 20 miles per hour.

The rotative motion of this great whirlwind was from the left to the right hand of a person entering it; or from right to left of a person leaving it; or contrary to the sun's apparent daily motion, or to the hands of a watch lying with the face upwards. That this was the actual motion was proved by the varying directions of the wind at the different points of its track, as also by its action on two outward-bound European ships, the Illinois and the Britannia. On the 15th August the Illinois experienced the swell which preceded the hurricane advancing from the south; but as tho ship had a fair wind, and was impelled by the Gulf Stream, while the storm lost time by making a bend towards Charleston and the coast of Georgia, the ship outran the swell; but on the 17th she was overtaken by the storm blowing furiously from south; while at the same moment it was tearing off the roofs of houses at New York, blowing from north-east. The Britannia, which

* In the records of various storms, the progressive movement has been found to vary from 43 to 3 miles an hour; and there is reason to think that storms sometimes move still more slowly, particularly between the tropics and lat. 30°, where they change their

direction.