Chagrined a little that we have hitherto been able to produce nothing in this way of use to mankind; and the hot weather coming on, when electrical experiments are not so agreeable, 'tis proposed to put an end to them for this season, somewhat humorously, in a party of pleasure, on the banks of _Skuylkill_.[4] Spirits, at the same time, are to be fired by a spark sent from side to side through the river, without any other conductor than the water; an experiment which we some time since performed, to the amazement of many. A turkey is to be killed for our dinner by the _electrical shock_, and roasted by the _electrical jack_, before a fire kindled by the _electrified bottle_; when the healths of all the famous electricians in _England_, _Holland_, _France_, and _Germany_, are to be drank in [5]_electrified bumpers_, under the discharge of guns from the _electrical battery_. _April 29, 1749._ [Illustration] LETTER IV. CONTAINING OBSERVATIONS _and_ SUPPOSITIONS, _towards forming a new_ HYPOTHESIS, _for explaining the several_ Phænomena _of_ THUNDER-GUSTS.[6] _SIR_, §. 1. Non-electric bodies, that have electric fire thrown into them, will retain it 'till other non-electrics, that have less, approach; and then 'tis communicated by a snap, and becomes equally divided. 2. Electrical fire loves water, is strongly attracted by it, and they can subsist together. 3. Air is an electric _per se_, and when dry will not conduct the electrical fire; it will neither receive it, nor give it to other bodies; otherwise no body surrounded by air could be electrified positively and negatively: for should it be attempted positively, the air would immediately take away the overplus; or negatively, the air would supply what was wanting. 4. Water being electrified, the vapours arising from it will be equally electrified; and floating in the air, in the form of clouds, or otherwise, will retain that quantity of electrical fire, till they meet with other clouds or bodies not so much electrified, and then will communicate as beforementioned. 5. Every particle of matter electrified is repelled by every other particle equally electrified. Thus the stream of a fountain, naturally dense and continual, when electrified, will separate and spread in the form of a brush, every drop endeavouring to recede from every other drop. But on taking out the electrical fire, they close again. 6. Water being strongly electrified (as well as when heated by common fire) rises in vapours more copiously; the attraction of cohesion among its particles being greatly weakened, by the opposite power of repulsion introduced with the electrical fire; and when any particle is by any means disengaged, 'tis immediately repelled, and so flies into the air.