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favour this humble attempt to waken the attention to a subject of such great national importance.
Dr. Franklin among the other inquiries that had engaged his attention, during a long life spent in the uninterrupted pursuit of useful improvements, did not let this escape his notice; and many useful hints, tending to perfect the art of navigation, and to meliorate the condition of seafaring people, occur in his work. In France, the art of constructing ships has tong been a favourite study, and many improvements in that branch have originated with them. Among the last of the Frenchmen, who have made any considerable improvement in this respect, is M. Le Roy, who has constructed a vessel well adapted to sail in rivers, where the depth of water is inconsiderable, and that yet was capable of being navigated at sea with great ease. This he effected in a great measure by the particular mode of rigging, which gave the mariners much greater power over the vessel than they could have when of the usual construction.
I do not hear that this improvement has in any case been adopted in Britain. But the advantages that would result from having a vessel of small draught of water to sail with the same steadiness, and to lie equally near the wind, as one may do that is sharper built, are so obvious, that many persons have been desirous of falling upon some way to effect it. About London, this has been attempted by means of lee boards (a contrivance now so generally known as not to require to be here particularly des cribed) and not without effect. But these are subject to certain inconveniences, that render the use of them in many cases ineligible.
Others have attempted to effect the purpose by building vessels with more than one keel; and this contrivance, when adopted upon proper principles, promises to be attended with the happiest effects.But hitherto that seems to have been scarcely adverted to. Time will be necessary to eradicate common notions of very old standing, before this can be ef fectually done.
Mr. W. Brodie, ship-master in Leith, has lately adopted a contrivance for this purpose, that seems to
be at the same time very simple and extremely efficacious. Necessity, in this case, as in many others, was the mother of invention. He had a small, flat, ill-built boat, which was so ill constructed as scarcely to admit of carrying a bit of sail on any occasion, and which was at the same time so heavy to be rowed, that he found great difficulty in using it for his ordinary occasions. In reflecting on the means tha* might be adopted for giving this useless cable such a hold of the water as to admit of his employing a sai when he found it necessary, it readily occurred tha a greater depth of keel would have this tendency. But a greater depth of keel, though it would have been useful for this purpose, he easily foresaw, would make his boat be extremely inconvenient on many other occasions. To effect both purposes, he thought of adopting a moveable keel, which would admit of being let down or taken up at pleasure. This idea he immediately carried into effect, by fixing a bar of iron of the depth he wanted, along each side of the keel, moving upon hinges that admitted of being moved in one direction, but which could not be bent back in the opposite direction. Thus, by means of a small chain fixed to each end, these moveable keels could be easily lifted up at pleasure; so that when he was entering into a harbour, or shoal water, he had only to lift up his keels, and the boat was as capable of being managed there, as if he had wanted them entirely; and when he went out to sea, where there was depth enough, by letting them down, the lee keel took a firm hold of the water, (while the other floated loose) and gave such a steadiness to all its movements, as can scarcely be conceived by those who have not experienced it.
This gentleman one day carried me out with him in his boat to try it. We made two experiments. At first, with a moderate breeze, when the moveable keels were kept up, the boat when laid as near the wind as it could go, made an angle with the wake of about thirty degrees; but when the keels were let down, the same angle did not exceed five or six de. grees; being nearly parallel with the course.
At another time, the wind was right a-head, a brisk breeze. When we began to beat up against it, a trading sloup was very near us, steering the same course with us. This sloop went through the water a good deal faster than we could: but in the course of two hours beating to windward, we found that the sloop was left behind two feet in three; though it is certain, that if our false keels had not been let down, we could scarcely, in that situation, have advanced one foot for her three.
It is unnecessary to point out to seafaring men the benefits that may be derived from this contrivance in certain circumstances, as these will be very obvious to them.
Notwithstanding the many fruitless attempts that have been made to discover a north-west passage into the South Seas, it would seem that this important geographical question is not yet fully decided; for at a meeting of the Academy of Sciences, at Paris, held on the 13th of November last, M. Bauche, first geographer to the king, read a curious memoir concerning the north-west passage. M. de Mendoza, an intelligent captain of a vessel in the service of Spain, charged with the care of former establishments favourable to the marine, has made a careful examination of the archives of several departments: there he has found the relation of a voyage made in the year 1598 by Lorenzo Herrero de Maldonada. There it appears, that at the entry into David's Straits, north lat. 60 degrees, and 28 of longitude, counting from the first meridian, he turned to the west, leaving Hudson's Bay on the south, and Baffin's Bay on the north. Arrived at lat. 65 and 297, he went towards the north by the Straits of Labrador, till he reached 76 and 278; and finding himself in the Icy Sea, he turned south-west to lat. 60 and 235, where he found a strait, which separates Asia from America, by which he entered into the South Sea, which he called the Straits of Anian. This passage ought to be, aç.
cording to M. Bauche, between William's Sound and Mount St. Elias. The Russians and Captain Cook have not observed it, because it is very narrow. But it is to be wished, that this important discovery should be verified, which has been overlooked for two centuries, in spite of the attempts which have been made on these coasts. M. Bauche calls this passage the Straits of Ferrer.
POSITIONS TO BE EXAMINED.
1. ALL food, or subsistence from mankind, arisės from the earth or waters.
2. Necessaries of life that are not foods, and all other conveniences, have their value estimated by the proportion of food consumed while we are employed in procuring them.
3. A small people with a large territory, may subsist on the productions of nature, with no other labour than that of gathering the vegetables and catching the animals.
4. A large people with a small territory, find these insufficient; and, to subsist, must labour the earth, to make it produce greater quantities of vegetable food, suitable to the nourishment of men, and of the animals they intend to cat.
5. From this labour arises a great increase of vegetable and animal food, and of materials for clothing; as flax, wool, silks, &c. The superfluity of these is wealth. With this wealth we pay for the labour employed in building our houses, cities, &c. which are therefore only subsistence thus metamorphosed.
6. Manufactures are only another shape into which so much provisisons and subsistence are turned, as were in value equal to the manufacture produced. This appears from hence, that the manufac turer does not, in fact, obtain from the employer. for his labour, more than a mere subsistence, inclu
ing raiment, fuel, and shelter; all which derive their value from the provisions consumed in procuring
7. The produce of the earth, thus converted into manufactures, may be more easily carried into distant markets, than before such conversion.
3. Fair commerce is where equal values are exchanged for equal, the expense of transport included. Thus, if it costs A in England, as much labour and charge to raise a bushel of wheat, as it costs B in France to produce four gallons of wine, then are four gallons of wine the fair exchange for a bushel jof wheat, A and B meeting at half distance with their commodities to make the exchange. The advantage of this fair commerce is, that each party increases the number of his enjoyments, having, instead of wheat alone, or wine alone, the use of both wheat and wine.
9. Where the labour and expense of producing both commodities are known to both parties, bargains will generally be fair and equal. Where they are known to one party only, bargains will often be unequal, knowledge taking its advantage of ignorance.
10. Thus he that carries a thousand bushels of wheat abroad to sell, may not probably obtain so great a profit thereon, as if he had first turned the wheat into manufactures, by subsisting therewith the workmen while producing those manufactures, since there are many expediting and facilitating methods of working, not generally known, and strangers to the manufactures, though they know pretty well the expense of raising wheat, are unacquainted with those short methods of working; and thence, being apt to suppose more labour employed in the manufacture than there really is, are more easily imposed on in their value, and induced to allow more for them than they are honestly worth.
11. Thus the advantage of having manufactures in a country does not consist, as is commonly supposed, in their highly advancing the value of rough materials, of which they are formed; since, though sixpennyworth of flax may be worth twenty shillings