It is known that Japan extends from about the thirtieth to the fortieth degree of north latitude; there cannot be an error of more than two degrees, which is about fifty leagues; so that, relying on one of our best maps, a pilot would be in danger of losing his track or his life.
As for the longitude, the first maps of the Jesuits determined it between the one hundred and fifty-seventh and the one hundred and seventy-fifth degree; whereas, it is now determined between the one hundred and forty-sixth and the one hundred and sixtieth.
China is the only Asiatic country of which we have an exact measurement; because the emperor Kam-hi employed some Jesuit astronomers to draw exact maps, which is the best thing the Jesuits have done. Had they been content with measuring the earth, they would never have been proscribed.
In our western world, Italy, France, Russia, England, and the principal towns of the other states, have been measured by the same method as was employed in China; but it was not until a very few years ago, that in France it was undertaken to form an entire topography. A company taken from the Academy of Sciences despatched engineers or surveyors into every corner of the kingdom, to lay down even the meanest hamlet, the smallest rivulet, the hills, the woods, in their true places. Before that time, so confused was the topography, that on the eve of the battle of Fontenoy, the maps of the country being all examined, every one of them was found entirely defective.
If a positive order had been sent from Versailles to an inexperienced general to give battle, and post himself as appeared most advisable from the maps, as sometimes happened in the time of the minister Chamillar, the battle would infallibly have been lost.
A general who should carry on a war in the country of the Morlachians, or the Montenegrins, with no knowledge of places but from the maps, would be at as great a loss as if he were in the heart of Africa.
Happily, that which has often been traced by geographers, according to their own fancy, in their closets, is rectified on the spot. In geography, as in morals, it is very difficult to know the world without going from home.
It is not with this department of knowledge, as with the arts of poetry, music, and painting. The last works of these kinds are often the worst. But in the sciences, which require exactness rather than genius, the last are always the best, provided they are done with some degree of care.