One of the most effectual means of perfecting and ennobling the soul, of raising it above terrestrial conditions, and bringing it near the higher spheres, is science. Study, labour to learn of nature, to comprehend the plans and the phenomena which surround you, to explain to yourselves the universe of which you form a portion, and your soul will grow in strength and wisdom. It is very sad to contemplate the shameful ignorance in which almost all humanity is sunk. The population of our globe numbers 1,300,000,000, and of all this multitude hardly 10,000,000 can be said to have studied the sciences, and really cultivated their minds. All the rest of mankind are abandoned to an intellectual passiveness, which almost reduces them to the level of the animals. The earth is but a vast field of ignorance. As far as knowledge is concerned, almost all men die as they were born, they have not added a single idea, a single branch of knowledge to those which their parents--themselves ignorant--have inculcated in their youth. Nevertheless, thanks to the labours of some few men of uncommon mind and energy, the knowledge we possess at the present time is immense, we have made great progress in the study of nature and its laws. We understand the mechanism and the regulation of the universe, we have learned to reject the fallacious testimony of our senses, we have discerned the courses of the different stars, which look so much alike, when they shine in the firmament by night. We know that the sun is motionless in the centre of our world, and that a company of planets, among which the earth figures, revolve around him, in an orbit whose mathematical curve has been precisely fixed. We know the cause of the days and nights, as well as that of the seasons; we can predict almost to a second the return of the stars to a certain point of their orbit, their meetings, eclipses, and occultations. The globe which we inhabit has been surveyed and explored with care which has hardly missed a nook of it. We know the causes of the winds and of the rains, we can point out the exact course of the sea-currents, and foretell the hour and the height of the tides all over the globe. We know why glaciers exist at the northern and southern extremities of the earth, and why other glaciers crown the great mountain heights. The movements of the earth, which formerly produced chains of mountains, and which at present occasion volcanic eruptions and earthquakes, are quite comprehensible to us. The composition of all the bodies which exist on the surface, or are hidden in the depths of the earth, has been fixed with certainty.