Your kind Letter of Sept. 27. came to hand but very lately, the Bearer having staid long in Holland.

I always rejoice to hear of your being still employ’d in Experimental Researches into Nature, and of the Success you meet with. The rapid Progress true Science now makes, occasions my Regretting sometimes that I was born so soon. It is impossible to imagine the Height to which may be carried in a 1000 Years the Power of Man over Matter. We may perhaps learn to deprive large Masses of their Gravity & give them absolute Levity, for the sake of easy Transport. Agriculture may diminish its Labour & double its Produce. All Diseases may by sure means be prevented or cured, not excepting even that of Old Age, and our Lives lengthened at pleasure even beyond the antediluvian Standard. O that moral Science were in as fair a Way of Improvement, that Men would cease to be Wolves to one another, and that human Beings would at length learn what they now improperly call Humanity.—

I am glad my little Paper on the Aurora Borealis pleas’d. If it should occasion farther Enquiry, & so produce a better Hypothesis, it will not be wholly useless—

I am ever, with the greatest & most sincere Esteem, Dear Sir, Yours very affectionately

I have considered the Situation of that Person very attentively; I think that with a little help from the Moral Algebra, he might form a better Judgment than any other Person can form for him. But since my Opinion seems to be desired, I give it for continuing to the End of the Term under all the present Disagreeable Circumstances. The Connection will then die a natural Death. No Reason will be expected to be given for the Separation, and of course no Offence taken at Reasons given. The Friendship may still subsist, and in some other way be useful.— The Time diminishes daily, and is usefully employ’d. All human Situations have their Inconveniencies. We feel those that we find in the present, and we neither feel nor see those that exist in another. Hence we make frequent & troublesome Changes without Amendment, and often for the Worse. In my Youth I was Passenger in a little Sloop, descending the River Delaware. There being no Wind, we were obliged, when the Ebb was spent, to cast anchor, and wait for the next. The Heat of the Sun on the Vessel was excessive, the Company Strangers to me & not very agreeable. Near the River Side I saw what I took to be a pleasant green Meadow, in the Middle of which was a large shady Tree, where it strook my Fancy, I could sit & read, having a Book in my Pocket, and pass the Time agreably till the Tide turned. I therefore prevail’d with the Captain to put me ashore. Being landed I found the greatest Part of my Meadow was really a Marsh, in crossing which to come at my Tree, I was up to the Knees in Mire: And I had not plac’d my self under its Shade five Minutes before the Muskitoes in Swarms found me out, attack’d my Legs, Hands & Face, and made my Reading & my Rest impossible: So that I return’d to the Beach, & call’d for the Boat to come and take me aboard again, where I was oblig’d to bear the Heat I had strove to quit, and also the Laugh of the Company.— Similar Cases in the Affairs of Life have since frequently fallen under my Observation.—

I have had Thoughts of a College for him in America. I know no one who might be more useful to the Publick in the Institution of Youth. But there are possible Unpleasantnesses in that Situation, it cannot be obtain’d but by a too hazardous Voyage at this time for a Family: And the Time for Experiments would be all otherwise engaged.