Benjamin Franklin Papers

To Benjamin Franklin from Cadwallader Colden, 16 March 1752

From Cadwallader Colden

Draft: New-York Historical Society

Coldengham March 16th 1752

Dear Sir

Last fall I acknowleged from New York the favour you did me in sending me a copy of your Electrical experiments.8 The oftener I read them over the more I am pleased with them and every time discover some thing new which I had not taken notice of at the first reading. In my opinion no set of experiments which I have read lead so directly towards discovering the cause of Electricity as yours do. However I find it difficult to form any conception of this cause which in any degree satisfies my mind. I conceive it to be a most subtile elastic fluid like our air but incomparibly more subtile and more elastic. Vinegar and Vinous spirits are both parts or productions of Fermented liquors. High rectified Spirit is an electric per se. Vinegar is a none Electric or a Conductor, Now I can easily Imagine that Wine or fermented Liquor contains a considerable quantity of this Electrical fluid [and] that Vinegar has lost it all or a great part of it but that the whole or greatest part is seperated with the high spirit and remains with it. But I cannot conceive how or from what cause it proceeds that in proportion as one side of the glass is filled with this elastic fluid the other side is emptied of it and without understanding this no satisfactory account can be given of the Phoenomena of Electricity.

You say that Salt is an electric per se. Several pieces of West India Salt will draw the electrical fluid from the electrified viol [vial] and some others will not do it. Some will draw off the Electricity from the viol even when they are fixed in sealing wax. Salts never communicat the Shock but seem to retain the Electrical fluid in themselves and become saturated with it. For by some experiment made in my house a piece of Salt that at first drew of the Electricity would by repeated applications to the Electrical viol become an electric per se. But all Electrical experiments depend so much on particular circumstances that any not so much conversant in them as you are may be easily deceived.

We have observed that Woemens flannel under petticots are sometimes deeply charged with the Electrical fluid so as in the Winter time after they are throun off and a non-electric draw slowly over them make a snapping noise as the excited tube does on the approach of a non electric.

I inclined to have made experiments by filling the viol at several times with the strong acid spirits such as strong spirit or oyl of Vitriol, Sp. of Niter, Aqua fortis and Aq. Regia and at other times with the Alcaline sp. as sp. of Sal Armen [Ammoniac], Hartshorn &c. but I have not sufficient quantities for such purposes.

I would incline likewise to make experiments on several kinds of Salts as common salt, Niter, Borax, and Ammoniac, of Earths as Bole, Chalk, Clay, Sand, Lime, &c. I am strongly inclined to think that from such like experiments we may learn many usefull things in Medecine and Agriculture. For I suspect that all Fermentations Vegetation and Animal Motion is principally produced by this subtile elastic fluid which I imagine to be the cause of Electricity and is more or less to be found in all bodies strongly, retained by some, and seperating easily from others. When the Viol has been repeatedly charged we find Water raised along the Wine to the outside of the Cork and may not the similar nourishment in plants be raised in such like manner.

I am so strongly possessed with the Principles of Action in Matter which you have seen that I amuse my self at leisure hours in applying them to the explication of the most general phoenomena of nature and can not easily direct my thoughts to other speculatives. These favourite prepossessions probably may be of advantage to our gaining of knowlege more perhaps than if you and I were both solely attached to one kind of pursuit because one may receive hints from the other which do not naturally arise in the pursuit which only one singly follows. Some gentlemen distinguished by their knowlege in Physical matters in London, Oxford, Leipsic, and Paris have given so favourable an opinion of that litle treatise that I have been induced to revise what was before wrote and to make considerable additions which I expect Mr. Dodsley9 has by this time printed a Specimen of the sheet I have received this spring. The printer has don his part to recommend it by a good letter and paper. I have indeavour to explain my thoughts more clearly and fully than I did at first. A few copies of it will be printed as it is not adapted to amuse common readers. I cannot expect that my sentiments so contrary to the commonly received notions should suddenly prevail. A French Gent. writes il a bien donné la torture a nos Metaphysiciens but I am confident they will at last.

I have mentioned this book on account of a proposition advanced in it which perhaps may be of use or serve as a hint for explaining the electrical fire.

I propose to add to this a copy of an illustration of that proposition because the illustration will not be found in the printed book.1

No doubt you have seen the Cure of Cancers by the Poke weed published in the Gentns. Magazine.2 I have lately had a confirmation of this by a Cancer last year cured in a Womans breast. I make no doubt it will generally make a perfect cure of a genuine Cancer from many Accounts. I have heard though not obtained in such an authentic manner as fit to be published and as no cure before this was known but by the cruel method of extirpation and that not allwise a certain cure publication in the Magazine may be of use to many miserable persons. Though this juice gives much pain in the application it is not a caustic but rather such kind of pain as Arum gives without destroying the substance of the flesh. I never heard of any ill consequence from the external use of it where the sick had patience to endure the pain tho it has been frequently used in external applications.

To Mr. Franklen

Endorsed: To Benj. Franklin Relative to Electricity

[Note numbering follows the Franklin Papers source.]

8See above, p. 200.

9James Dodsley (1724–1797), bookseller of Pall Mall, printed Colden’s revised work on gravitation under the title The Principles of Action in Matter, the Gravitation of Bodies, and the Motion of the Planets, explained from those Principles, 1751.

1Not found.

2The article, by “an eminent physician at New-York,” detailed several cures of cancer in Connecticut, by use of phytolacca or pokeweed, reports of which were sent to the author (Cadwallader Colden?) at his request, by Rev. Dr. Samuel Johnson of Stratford, Conn. Gent. Mag., XXI, (1751), 305–8. See also Colden Paps., III, 121, 123–5, 128–9.

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