any one to make the meridians for the globe, and its other appurtenances.
"With the little camera obscura, which you had the kindness to send me, I have already learned perspective drawing to my own satisfaction. I have practiced on churches, houses, etc. If I were among the lifting machines in Fahlun or elsewhere, I could make drawings of them as well as any one else, by means of this little instrument."
Here we have a man perfectly equipped for eminent success in the highest range of philosophical inquiry, who, in the short space of five or six years, makes himself practically acquainted with seven of the industrial arts,—book-binding, music, the manufacture of watches, furniture, and mathematical instruments, engraving, perspective drawing; no one of which in the days of Plato would have been, and scarcely now is, thought a desirable acquisition for a gentleman. At the comparatively early age when these letters were written, Swedenborg was coming, unconsciously, perhaps, under the dominion of the great principle which he lived afterwards to illustrate with singular efficacy, both by precept and example, that the only genuine happiness this life or any other can yield, results from efforts to promote the welfare of others.
When he published his Opera Philosophica et Mineralia, in which he gave with considerable detail the theoretical and practical process of copper and iron melting, he was taken to task by others in the business, for revealing its mysteries to the public. Speaking of these censors in one of his letters, he writes:—"There are some who love to hold knowledge for themselves alone, and to be reputed possessors and guardians of secrets. People of this kind grudge the public everything; and if any discovery by which Art and Science will be benefited comes to light, they look at it askance with scowling visage, and probably denounce the discoverer as a babbler, who lets out secrets. Why should secrets be grudged to the public? Why withheld from this enlightened age? Whatever is worth knowing should by all means be brought into the common market of the world. Unless this be done we can neither grow wiser nor happier with time."