The second period of Swedenborg's life was devoted to the study and the practical application of Natural Science. His rare gifts for mathematics and mechanics soon won for him the favor of the young king Charles XII, the office of Assessor of Mines, and a patent of nobility, with a seat in the upper house of the Swedish Parliament.
On leaving the university, and while preparing for a prolonged sojourn in England, to perfct his education, he revealed, in a letter to his brother-in-law, Benzelius, the bent his mind had already received towards the study of mathematics. " · · · And now at my departure," he wrote, "I propose to myself, gradually to gather and work up a collection of things discovered and to be discovered in mathematics, or, what is nearly the same thing, to measure the progress made in mathematics during the last one or two centuries. This collection will include all branches of mathematics, and will I trust be of use to me during my journeys."
In his twenty-first year he was sent to England, where on less than $200 a year he spent between two and three years in the prosecution of his favorite study, and its application to the sciences of astronomy and mechanics,—seeking the acquaintance and frequenting the society of those who were presumed to be masters of those sciences. Writing to Benzelius, soon after his arrival in London, he says: "I study Newton daily, and am very anxious to see and hear him." Sir Isaac Newton at this time was in his seventieth year, and president of the Royal Society, of which Sir Hans Sloane was secretary. Swedenborg goes on: "I have provided myself with a small stock of books for the study of mathematics, and also with a certain number of instruments, which are a help in the study of science. I hope that, after settling my accounts, I may have sufficient money left to purchase an air-pump."
He writes again in April following, to Benzelius, who was librarian of the University at Upsala: