I now send back to you Wilson on Electricity for the use of which I am much obliged. My youngest son the only one I have with me hopes to be able to make Electrical experiments tollerably well. Mr. Wilson I think is on the true scent of the cause of Electricity though it be plain he is not sufficiently informed of the nature of that elastic fluid which he calls Aether to be able sufficiently to account for the Phaenomena. In my Opinion some more perfect knowledge of the Air than we have is likewise necessary and the cause of the cohesion of the parts of bodies which last has been lately the subject of my Meditations. No tollerable account of this so far as I know has been given by any Philosopher and if this can be accounted for from my Principles it will go a great way to confirm them. I hope to let you see something on this head. At present I shall only mention one Theorem viz. That the parts or particles of Bodies are at a great distance from each other in the ratio of their bulk. To prove this it is supposed that the solid particles of inert Matter are impenetrable by light or that Light cannot be in the same space with matter. Then since light freely passes through pellucid bodies in streight lines and in all directions with a very small diminution of its quantity, the distance between the particles of pellucid bodies must be very great in proportion to their bulk if the prodigious number of those particls be considered which must be in a pellucid body of any bulk. This may be easily conceived by placeing a number of points in any order and considering how they must stop the progress of light in many directions. Again the number of particles in the same quantity of space in several bodies is as their Specific Gravities. Now considering the difference of Specific Gravity of pellucid bodies and of any other opac body that it does not arise to a great degree the parts of all bodies must be at a great distance from each other in proportion to their bulk. Sir Isaac Newtone accounts for the cohesion of the parts of bodies from the stronger attraction in litle bodies than in great bodies but if this were the cause the parts of bodies must run together into mutual contact if some other power do not keep them seperated. What I call Aether is essentially different from Mr. Wilson’s Aether and from that Elastic fluid which I think produces Electrical phaenomena. Sir Isaac Newtone was far from having clear conceptions of what I call Aether though he perceived from the Phaenomena that some such medium must necessarly exist between the several bodies in the Universe and within them between their component parts.

I have at last got the remarks on the First causes of Action in Matter well translated by Mr. Hartwick a Lutheran Minister who is well acquainted with the German systems of Philosophy and thereby more capable of making a good Translation. I have likewise drawn up an answer to the remarks which I expect may assist you to form a better conception of my principles and of the truth of them than what you have allready seen. I now send both the remarks and Answer to Mr. Alexander and I shall desire him to transmit them to you if he do not think it necessary to alter any thing in the Answer. In the mean time I send you the original remarks in the German language that you may the better judge of the Translation when you shall see it.

The Remarks and Answer are chiefly on the Metaphysical parts of my System. The same subject is treated in Dr. Johnson’s Noetica but in a very different manner. I hope from your Friendship that you will give me your sentiments without reserve and I beg that you will take some pains because I have some distant prospect of being able to explain the phaenomena of Electricity from my Principles with your assistance. If this can be don I am perswaded that the greatest improvement will thereby be made in the most usefull parts of Physics. I conceive that Fermentations of all sorts arise from Electricity and that the life and vegetation of Animals and Vegetables arise from Fermentation. If so the knowlege of Electricity must give great light in Medecine and Agriculture. For this reason I will gladly take pains to remove any difficulties you may have in receiving or conceiving these Principles. I have not as yet heard that the Principles of Action in Matter is published though I had the first sheet sent me in January last.