lofophers were difpofed to account for the phenomena, rather from a difference in the quantity of electricity collected; and even Du Faye himself feems at laft to have adopted this doctrine, Franklin at firft entertained the fame idea; but upon repeating the experiments, he perceived that Mr. Kinnerfley was right; and that the vitreons and refinous electricity of Du Faye were nothing more than the positive and negative states which he had before observed; that the glass globe charged pofitively, or increafed the quantity of electricity on the prime conductor, whilft the globe of fulphur diminished its natural quantity, or charged negatively. These experiments and obfervations opened a new field for invefti gation, upon which electricians entered with avidity; and their labours have added much to the stock of our knowledge.

In September 1752, Franklin entered

upon

upon a course of experiments, to deter mine the state of electricity in the clouds, From a number of experiments he formed this conclufion : "that the clouds of a thunder-guft are most commonly in a negative state of electricity, but fometimes in a pofitive ftate;" and from this it follows, as a neceffary confequence," that, for the moft part, in thunder-ftrokes, it is the earth that ftrikes into the clouds, and not the clouds that ftrike into the earth." The letter containing thefe obfervations is dated in September 1753; and yet the discovery of afcending thunder has been faid to be of a modern date, and has been attributed to the Abbe Bertholon, who publifhed his memoir on the fubject in 1776.

Franklin's letters have been tranflated into most of the European languages, and into Latin. In proportion as they. have become known, his principles have

been

been adopted.

Some oppofition was

made to his theories, particularly by the Abbe Nollet, who was, however, but feebly fupported, whilft the firft philofophers of Europe stepped forth in defence of Franklin's principles; amongft whom D'Alibard and Beccaria were the most diftinguished. The oppofition has gradually ceafed, and the Franklinian fyf tem is now univerfally adopted, where fcience flourishes.

The important practical ufe which Franklin made of his discoveries, the fecuring of houfes from injury by lightning, has been already mentioned. Pointed conductors are now very com. mon in America; but prejudice has hitherto prevented their general introduction into Europe, notwithstanding the moft undoubted proofs of their utility have been given. But mankind can with difficulty be brought to lay afide eftablished practices, or to adopt new

ones,

ones.

And perhaps we have more reafon to be surprised that a practice, however rational, which was proposed about forty years ago, fhould in that time have been adopted in fo many places, than that it has not univerfally prevailed. It is only by degrees that the great body of mankind can be led into new practices, however falutary their tendency. It is now nearly eighty years fince inoculation was introduced into Europe and America; and it is fo far from being general at prefent, that it will, perhaps, require one or two centuries to render it fo.

In the year 1745, Franklin published an account of his new-invented Pennfylvania fire-places, in which he minutely and accurately states the advantages and difadvantages of different kinds of fireplaces; and endeavours to fhew that the one which he defcribes is to be preferred to any other, This contrivance has given rife to the open ftoves now in general

general use, which however differ from it in conftruction, particularly in not hav ing an air-box at the back, through which a conftant fupply of air, warmed in its paffage, is thrown into the room. The advantages of this are, that as a stream of warm air is continually flowing into the room, less fuel is neceffary to preserve a proper temperature, and the room may be fo tightened as that no air may enter through cracks; the confequences of which are colds, toothaches, &c.

Although philofophy was a principal object of Franklin's purfuit for feveral years, he confined himself not to this. In the year 1747, he became a member of the general affembly of Pennsylvania, as a burgefs for the city of Philadel phia. Warm difputes at this time fubfifted between the affembly and the proprietaries; each contending for what they conceived to be their juft rights. Franklin, a friend to the rights of man from his infancy,