In the year 1765, when the duke of Courland, then hereditary prince, resided at Berlin, he paid a visit to Hohlfeld, and endeavoured to prevail on him to go to Courland, by offering him a pension of 800 rix-dollars; but this ingenious man was so contented with his condition, and so attached to his friends, that he would not, merely for self-interest, quit Berlin. His refusal, however, obtained for him a pension of 150 dollars from the king. Besides the before-mentioned machines, he constructed, occasionally, several useful models. Among these were a loom for weaving figured stuffs, so contrived that the weaver had no need of anything to shoot through the woof[25]; a pedometer for putting in the pocket; a convenient and simple bed for a sick person, which was of such a nature, that the patient, with the least effort, could at any time raise or lower the breast, and when necessary convert the bed into a stool; and a carriage so formed, that if the horses took fright or ran away, the person in it could, by a single push, loosen the pole and set them at liberty. The two last models have been lost. Every machine that this singular man saw, he altered and improved in the simplest manner. All his own instruments he made himself, and repaired them when damaged. But as he was fonder of inventing than of following the plans of others, he made them in such a manner that no one except himself could use them. Several of his improvements were, however, imitated by common workmen, though in a very clumsy manner. It is worthy of remark, that he never bestowed study upon anything; but when he had once conceived an idea, he immediately executed it. He comprehended in a moment whatever was proposed, and at the same time saw how it was to be accomplished. He could therefore tell in an instant whether a thing was practicable; if he thought it was not, no persuasion or offer of money could induce him to attempt it. He never pursued chimæras like those mechanics who have not had the benefit of education or instruction; and though this may be ascribed to the intercourse he had with great mathematicians and philosophers, there is every reason to believe that he would have equally guarded against them, even if he had not enjoyed that advantage. The same quickness of apprehension which he manifested in mechanics he showed also in other things. His observations on most subjects were judicious, and peculiar to himself; so that it may be said, without exaggeration, that he was born with a philosophical mind.