After an absence of fifteen months, Swedenborg returned to his home in Stockholm, at midsummer, 1722. He now for the first time entered fully upon the duties of his Assessorship; having deferred doing so until his knowledge of metallurgy had become sufficiently practical and extensive. At this time he published an anonymous pamphlet “On the Depreciation and Rise of the Swedish Currency.” The currency seems to have been a favorite subject with Swedenborg; and in his senatorial capacity, it engaged much of his attention. The pamphlet seems to have been much thought of, for we find that it was republished at Upsal in 1771. There are few productions of this kind that will endure a revival forty-nine years after their first publication. The tenor of Swedenborg’s life for eleven years after this, seems to have flowed quietly on in the regular fulfilment of the duties of his office. It may be supposed that he had become tired of writing and publishing scientific works, and that for a time he wished to rest from this kind of labor. His abilities were appreciated by his countrymen, for we find that he was solicited to accept the Professorship of mathematics in the University of Upsal, in 1724. He declined the honor. It appears that he had a distaste for the unpractical and merely speculative character of the pure mathematician. We find him writing to his brother-in-law in this strain:—“I wonder at Messieurs the mathematicians having lost all heart and spirit to realize that fine design of yours for an astronomical observatory. It is the fatality of mathematicians to remain chiefly in theory. I have often thought it would be a capital thing, if, to each ten mathematicians, one good practical man were added, to lead the rest to market: he would be of more use and mark than all the ten.” In 1729, Swedenborg became a member of the Royal Academy of Science at Stockholm. Discontinuing the pamphlet style of publication, Swedenborg now centered his thoughts upon the production of a much larger and more laborious work than he had hitherto attempted. It was entitled “Opera Philosophica et Mineralia.” In order to secure its proper publication, he went abroad, for the third time, in May, 1733. After spending five months in Germany, seeing everything note-worthy, he commenced the printing of his work at Leipsic, in the month of October. In the course of the year 1734, the whole was finished in three handsome folio volumes, enriched with numerous copper-plates, and an engraved likeness of the author. At this time he was again a visitor at the court of the Duke of Brunswick, who munificently defrayed the cost of his expensive publication. The volumes were published at Leipsic and Dresden. At the same time he issued a little work called “A Philosophical Argument on the Infinite, and the Final Cause of Creation; and on the Mechanism of the Intercourse between the Soul and the Body.” It may be regarded as a supplement to the foregoing.