For ourselves we are by no means satisfied that there is yet any theory of electricity which will “suit _all_ the facts;” and therefore if this be requisite to entitle a theory _philosophy_, as contra-distinguished from _hypothesis_, we must think that the best theory of electricity is yet hypothesis, and not philosophy. We believe that the Franklinian theory accounts for _more_ facts, and is far more plausible, than any other. But, as we have already had occasion to remark in a former chapter, it does not appear to us fully and satisfactorily to account for all the phenomena of electric attraction and repulsion. Dr. Franklin always spoke with great diffidence of his own theory, and always denominated it an hypothesis. “Every appearance, says he, which I have seen, in which glass and electricity are concerned, are, I think explained with ease by this _hypothesis_. Yet, perhaps, it may not be a true one, and I shall be obliged to him who affords me a better.” In like manner Æpinus, who adopted the theory of Franklin, and who has illustrated its leading principles in a far more masterly and scientific manner than any other writer, still denominates the theory which he maintains an _hypothesis_. Why should pupils affect to go farther than their masters? We think that the theory of electricity is still an hypothesis. We are however clearly of opinion that the hypothesis of Franklin is preferable to every other. We have therefore adopted it in the whole of our system, and mean to close this division of our subject by giving it, somewhat in detail, with the leading facts and considerations by which its claim to superiority appears to us to be supported. In the mean time, as every student of electricity may wish to know, and ought to know, what other theories have been adopted, we shall fill the following chapter with a brief and compendious recital of some of the principal of them.—It would be endless to recite them all. We shall, however, enter into no extensive argument to prove their fallacy, as this would be inconsistent with our plan, as well as unprofitable in itself. We shall afterwards say what we can to confirm the theory of Franklin, and if we succeed, every thing opposed to it, must, of course, appear to be unsupported. CHAP. II. _Theories of Electricity, exclusive of that of Franklin._