Mr. Peter Collinson, F.R.S. London.
Philadelphia, July 29, 1750
SIR,
As you first put us on electrical experiments, by sending to our library company a tube, with directions how to use it; and as our honourable proprietary enabled us to carry those experiments to a greater height, by his generous present of a compleat electrical apparatus; 'tis fit that both should know from time to time what progress we make. It was in this view I wrote and sent you my former papers on this subject, desiring, that as I had not the honour of a direct correspondence with that bountiful benefactor to our library, they might be communicated to him through your hands. In the same view I write, and send you this additional paper. If it happens to bring you nothing new (which may well be, considering the number of ingenious men in Europe, continually engaged in the same researches) at least it will show, that the instruments, put into our hands, are not neglected; and, that if no valuable discoveries are made by us, whatever the cause may be, it is not want of industry and application.
I am, Sir,
Your much obliged
Humble Servant,
B. FRANKLIN.
OPINIONS and CONJECTURES,
Concerning the Properties and Effects of the electrical Matter, arising from Experiments and Observations, made in Philadelphia, 1749.
§ 1. The electrical matter consists of particles extreamly subtile, since it can permeate common matter, even the densest metals, with such ease and freedom, as not to receive any perceptible resistance.