I have just returned from a journey into Montgomery County or your letter of the 1st. Instant would have been answered Sooner. I send enclosed Captn. Lewis’s Catalogue.

The specimen of your improvement on the Pen-case shews that the nibs may be held firm, which was wanting in those made by my workmen. and altho’ I have at some expense got a Tool to make the large Screw with a finer thread than was to the Pen-arms I send you, which gives us the advantage of making the work considerably lighter, yet I believe that the first mode of mooving the Pen is preferable in such cases were a screw is required, in the common Polygraphs I shall give Mr. Hawkins mode.

The Polygraph’s you mean for Tripoli shall be made in the best manner. The silver work for the Machinery will be put into the hands of an Ingenious Silver-Smith Mr. Abraham DeBois—on tomorrow—but I wish to know if the furniture of Box (Hinges, Locks &c) must also be made of Silver? Instead of the vineered work, were we wanted good workmanship, we have put plates of Brass at all the Corners, which in my opinion is preferable, for however well the Cabinet Maker may do his work, yet if by accident the Machine is exposed to great moisture the fineering will come off. perhaps plated work would serve on the outside should you prefer it to the vineering? your postscrip shews your aprobation of solid work, which I had not attended to while writing on the other side. I am sorry to give you so much trouble when I know how precious your moments are: yet permit me to ask your advice about the size which may be best for these presents—I have made two Polygraphs which measure between the Gallows 17 Inches, which is a little larger than your small one. This size unites several important advantages; The part to be wrote on being smaller and yet of the same thickness of the foolscap size, is less liable to warp. I presume you have ment them to be with two Pens, as you have not mentioned three. The size for writing with more than two Pens must be large and therefore cumbersome, only fit for an office or counting-House.

The Marmot sleeps, and the Magpie chatters a great deal. Now alive in the Museum several interresting animals—The Crown bird (oiseau Royal), the Crowned Pidgion, American Magpie, a Ringtail Macoco, and a Syrin or Mud-Inguana of a large size from Georgia &c. The Philosophical Society possessing the Skeleton of an Elephant, I hope Doctr. Wistar will give the Public a comparative view of that with the Mammoth. I want you much to see these Skeletons together. Accept my best wishes for your health &c