Societies, afford a very respectable specimen of the talents and erudition of our countrymen, and hold up to view several names with distinguished ho

nour.

CHAPTER VII.

NAVIGATION.

NAVIGATION, considered both as an art and a science, was greatly advanced during the late century. This advancement was owing to a variety of circumstances, which are worthy of being transiently noticed in the present sketch.

The Construction of Ships has received, in modern times, very considerable improvements. That method of building which is favourable to rapid sailing, has been, for a number of years, gaining ground, in place of the old method, in which capacity was chiefly consulted. New and advantageous plans of rigging vessels have been adopted, and better modes of working them than were formerly in use. In the science of naval architecture, and of navigation generally, perhaps no individual has done more to useful purpose than EULER, of whose ingenious and excellent labours, in several departments of science, we have had frequent occasion to speak. In consequence of his celebrated publications on this subject, the mathematicians of France were incited to study the

s The first volume on the higher branches of the mathematics ever presented to the public by a native American, made its appearance in the course of the current year (1802), under the title of Essays, Mathematical and Physical, by JARED MANSFIELD, of New-Haven, Connecticut. This writer displays a degree of mathematical genius and erudition which does honour to himself and his country.

theory of ship-building, by which means nautical science in that country made remarkable progress. A taste for the same species of inquiry afterwards began to grow in Great-Britain; and under the auspices of the government of that country, and various public societies, has since produced many important improvements.

In estimating the revolutions which took place in naval architecture in the course of the last age, perhaps few are more signal than the great increase in the dimensions of ships of the same rate. Ships of war, in particular, are now generally a fourth, and, in many cases, a third larger than vessels of the same number of guns were at the beginning of the late century. In this augmentation the naval architects of France took the lead, and have gone the greatest lengths; the British followed their example, and have carried every thing which relates to the construction and management of ships to a great degree of perfection.

While modern ships are larger than the ancient, they are at the same time more light and simple in their structure. The cumbrous and useless ornaments which the false and unphilosophical taste of preceding ages employed, have been laid aside; and, in general, those principles of architecture adopted which combine the advantage of easy management with the greatest burden..

The Mariner's Compass, though it has been it use for several centuries, was attended with great imperfections and inconveniencies until a few years ago, when Dr. GowIN KNIGHT, of GreatBritain, in consequence of his invention of Artificial Magnets, was enabled considerably to improve this inestimable instrument. The compasses made by him were found to exceed, in regularity. and exactness, all those which had been constructed before his time. After him further im

provements of importance were made by Mr. SMEATON, and Mr. M'CULLOCH, also of GreatBritain. The complete Azimuth Compass is one of the most valuable presents which modern genius has made to navigators.

The compass is scarcely of more importance to the mariner, than the celebrated invention of the Quadrant, commonly ascribed to Mr. HADLEY, of Great-Britain, but of which the honour really belongs to Mr. GODFREY, a philosophic artist of Philadelphia. To which may be added the numerous improvements of this instrument, some of which were mentioned in another place; to say nothing of many others, under the names of Sectants, Octants, &c. constructed on like principles, and for similar purposes.

Almost all the methods now in use for finding the Longitude, whether by means of Lunar Observations, the position of Jupiter's Satellites, or of well constructed Time-keepers, were first brought into general use during the last century. The rise, progress, and authors of these several discoveries and improvements were briefly detailed in a former chapter. The important place which they hold in the annals of navigation is too generally understood to require formal elucidation.

The invention of Ephemerides, or Nautical Almanacks, is another important event which belongs to the century under review. They were first published for the use of mariners, by M. DE LA CAILLE, about the year 1755. Dr. MASKELYNE, in England, followed his example, and first published them in that country, about the year 1767. The effects of these almanacks in advancing the art of navigation is well known. Their influence in promoting the Lunar method of finding the longitude is worthy of particular remark. The extreme facility with which that operation, for

merly so tedious and difficult, is now performed, even by common seamen, deserves to be noticed as a distinction of the age under consideration.

The great augmentation in the number of Maps and Charts, and the manifest improvements in their construction, accuracy, and elegance, may also be mentioned among the circumstances, in modern times, which have contributed to the advance- . ment of navigation. The degree in which these improvements have promoted the safety, the comfort, and the expedition of late voyages, is scarcely within the reach of ordinary calculation.

But there are few modern improvements in the art of navigation more gratifying to humanity than the remarkable and very successful attention to the Health of Seamen, which characterizes the conductors of late voyages. The names of those who distinguished themselves by devising and bringing into use the most approved methods for promoting this end were respectfully mentioned in a preceding division of this work. The great contrast which the history of ancient and modern voyages presents with respect to the comparative destruction of the health and lives of mariners which they produced, cannot but forcibly arrest the attention of every reader, and exceedingly gratify the benevolent mind. Besides the improvements in diet and regimen on ship-board, to which modern science and humanity have given rise, and which have contributed greatly to preserve the health of seamen, the introduction of Ventilators into ships also deserves to be mentioned as an important means of promoting the same object, and, at the same time, for preserving the timber and cargoes of vessels. To these may be added

+ For the invention of one of the most complete and useful plans for ventilating ships, we are indebted to our ingenious countryman, Mr. WYNKOOP, of Philadelphia, whose contrivance for this purpose has received high praise from those who are most competent to judge of its merits.

some notice of the modern improved methods of constructing Pumps, and other hydraulic machinery of ships, by which the safety and comfort of navigators are greatly secured.

In addition to the improvements which have been mentioned, some notice might be taken of the various plans for promoting Sub-marine Navigation, which have been laid before the public at different times, and by different persons in the course of the last age; of the attempts to construct Lifeboats, for the safety of mariners in cases of extremity; of the improved methods which have been invented for facilitating the guidance of ships on the ocean, and for measuring their progress. But to give an intelligible enumeration of these and of many other modern improvements in navigation would lead to a minuteness of detail inconsistent with the plan of the present sketch.

Besides many ingenious individuals to whom mariners are indebted for patronizing and aiding their art, much is also due to some learned and other societies, for their useful exertions to promote the same end. But perhaps to no public bodies will the annals of modern navigation be found to ascribe more than to the Board of Longitude, and the Board of Admiralty of Great-Britain.

From the concurring influence of all the considerations above stated, enterprising men have learned, within the eighteenth century, to traverse the most distant seas, with a degree of ease, confidence and expedition, wholly unknown in any former age. A voyage from Europe or America to India, is now performed in half the time that it cost an hundred years ago; and even a voyage round the world is considered at present as an undertaking scarcely more formidable than a voyage from America to Europe at the beginning of the century in question.