To James Bowdoin
ALS: Massachusetts Historical Society
Philada. April 12. 1753
I have shipt 18 Glass Jarrs in Casks well pack’d, on board Capt. Branscombe for Boston. 6 of them are for you, the rest I understand are for the College. Leaf Tin, such as they use in silvering Looking Glasses, is best to coat them with; they should be coated to within about 4 or 5 Inches of the Brim.7 Cut the Tin into Pieces of the Form in the Margin, and they will comply better with the Bellying of the Glass, one Piece only should be round to cover the Bottom; the same Shapes will serve the Inside. I had not Conveniency to coat them for you, and feared to trust any body else, Mr. Kinnersly being abroad in the W Indies. To make the Pieces comply the better they may be cut in two where the cross Lines are. They reach from the Top, to the Edge of the round Piece which covers the Bottom. I place them in loose Rims of Scabboard8 something like a small Sieve, in which they stand very well. If you charge more than one or two together, pray take care how you expose your Head to an accidental Stroke; for I can assure you from Experience, one is sufficient to knock a stout Man down; and I believe a Stroke from two or three in the Head, would kill him.
Has Dr. Colden’s new Book reach’d you in Boston.9 If not, I’ll send it to you.
With great Respect, I am, Sir Your most humble Servant
The Glassmaker being from home, I cannot now get the Account.
The Tin is laid on with common Paste made of Flour and Water boil’d together and the Pieces may lap over each other a little.
7. For illustrations of the kinds of Leyden jar BF used, see above, III, 160–1. A battery of his jars, now in APS, is shown in I. Bernard Cohen, Franklin and Newton (Phila., 1956), following p. 454.
8. Scabboard (scaleboard): a very thin slip of wood or cardboard used by printers to justify type.
9. Cadwallader Colden, The Principles of Action in Matter (London, 1751). Writing Colden the same day (see immediately below), BF asked for a copy to send Bowdoin.