David Hartley to Benjamin Franklin, September 26, 1781

Margate Sept 26 1781

My Dear friend

Having an opportunity of a conveyance to you, I write one short line (as my notice is very sudden and short) just to tell you how happy I shd have been to have had an opportunity of seeing and Conversing with you. I fear that pleasure must be delayed, but it wd make me infinitely happy to look forward to that pleasure upon some future occasion.— 7 At present the particular occasion of this letter, is to suggest to you a plan, of preventing the horrid consequences of fire in opera houses & play houses. I mean as far as relates to the lives & safety of the spectators. 8 The general idea is this, viz to have a screen of fire plates where the green curtain hangs, to shut like a common scene, upon any alarm of fire—to put fire plates under the floor of the parterre & boxes, if hollow underneath; and likewise over the cieling and sounding board. The other three sides of that space wch contains the spectators, are of course built of brick or stone, & impenetrable to fire. This is the plan in general. I will send you drawings & a farther detail, & thro your means to Monsr Le Comte D’Angivilliers. 9 I will only add that I have tried the security of the firescreen at least an hundred times, with the most intense fires, and have always found them proof. The Canvass, and oil, & woodden frames, & all the combustibles of a play house, can never be made fire proof, but all lives may be saved— verbum sapiente—So much for the present I am always your affecte

D H