From Francis Hopkinson, with Enclosure
Philada. 20th. March 1785
Your Favour of the 11th Novr. came to Hand not long since, for which I thank you. I had, much about the same Time, written to you giving an Account of my further Improvement in the Method of Quilling a Harpsichord and enclosed a Model in my Letter. My Harpsichord quilled in this Way has been freely used by myself and Daughters since its Arrival last fall and not one Quill has failed, the Touch remaining perfect as at first so that I am sure the Discovery is a real One and is certainly of considerable Importance to Performers on that Instrument. About a Year and a half ago, I thought of a Method to improve the Tone of a Harpsichord. The Experiment was easily tried and I had myself little Doubt of the Success. I wrote an Account of it to my Correspondent in London but did not minutely describe the Process. He either did not, or would not understand me. Perhaps it may appear hereafter as a British Discovery. I was discouraged and the Idea remained unnoticed, till lately when it again reviv’d with some Vigour and claim’d my further Attention. I brought it to the Test last Evening. I invited several philosophical Gentlemen to my House, performed the Operation on my new Harpsichord in their Presence, and submitted it to their critical Examination. They declared in Favour of the Experiment. Amongst these Judges were Dr. Moyse the blind philosopher, Mr. Rittenhouse, Mr. Marbois, Mr. Vaughan &c. I will enclose full Directions for performing this Experiment, with a View that you would try it and give me your Opinion of the Result. But I wish you would keep the Secret for a Time at least, as I mean to make further Essays on other Instruments, and when I shall have fully ascertained the Fact, will communicate it to our philos: Society for publication in their next Volume. This Injunction however is not intended with respect to Dr. Franklin. I should be very glad if he would try the Experiment with you, if he thinks it worth his attention. By the Bye, I have not received a Line from him since you left us. Neither have I or Mr. Rittenhouse received the Pamphlets you were so good as to send us, but we have long since heard of the Fate of Animal Magnetism and seen the Report of the Commissioners thereon.
I have mentioned Dr. Moyse. I will now tell you who he is. He is a Scotchman by Birth and a Philosopher by Profession. He came to America from England with the famous Mrs. Haley. He arrived I believe about a Year ago at Boston and has come from thence to this City, giving public Lectures in Natural philosophy all the way. He spent the beginning of this Winter at New York, where he became very popular and a great favourite of the Ladies in particular who crowded to his Lectures, and happy was she who [could] get him to dine or drink Tea at her House. Having gone thro’ his Course there and reaped no small Honour and Profit, he is now performing with us. But the Rage for philosophy at New York, is not to be compared with that of Philadelphia. He exhibits three Evenings in a Week in the College Hall, he has already given 10 or a Dozen Lectures to an Audience of not less than 10 and most commonly 1200 Persons. The Ladies are ready to break their Necks after him. They throng to the Hall at 5 o’Clock for places, altho’ his Lecture does not begin till 7. He has been blind from his Infancy, has made Philosophy his Study and is well acquainted with the present admitted Systems, adding sometimes Theories of his own, which he does however, with rather too much Arrogance.
Our philos: Society are as dull as ever. There was a large Election of members last January. I took Care that our friend Mr. Maddison should be one of them. The publication of a Second volume of their Transactions is at length thrown into the hands of Mr. Patterson and myself and I do verily believe, it will e’er long be put to the Press.
I say nothing about Congress and their Proceedings. You will receive all Intelligence of that kind either officially or from your political friends.
I had the Misfortune to loose my dear Sister Morgan. She died on the first of January last. My Mother has given up House keeping and for the present lives with Dr. Morgan. They both din’d with me today and join in kind Remembrance to you and Love to your Daughter.
I hope to hear from you before this gets to hand and after too. With respectful Regards to Doctor Franklin I am Dear Sir, as ever Your affectionate friend and very humble Servt.,
I enclose for your Amusement one of my literary Gambols occasioned by a News paper Quarrel between Dr. Ewing and Dr. Rush, in which the broad Bottom of the University was too frequently mentioned. Mr. Bentley the Harpsichord Player and Mr. Brown the flute player have also had a Quarrel which they brought on the public Theatre. The enclosed turned the laugh of the Town upon all the Combatants and put an End to the War.
Since writing the above I have received the Pamphlets from Virginia for which I thank you.
Account of an Experiment made with a View to improve the Tone of a Harpsichord.
The Octave Stop of the Harpsichord being drawn off, we searched for two Unisons which were quilled as nearly alike as possible. These were perfectly tuned to each other. I then took a pair of strong Steel Magnets and laid them along Side of each other, the North Pole of one to the South Pole of the other. I seperated the lower Extremities of the Bars about an Inch, by Means of a Piece of folded Paper introduced between them; their upper Ends still remaining in Contact. Holding the Magnets in a perpendicular Position I applied their lower or seperated Ends to the steel String of one of the Unisons, and passed it gently along the whole length of the String four or five Times, whereby it became highly Magnetic. We then carefully compared the Tone of the String so magnetised with its Comparison which had not been touch’d and found it manifestly improved. The Vibrations being, or seeming to be, much more uniform and sweet to the Ear. This is a nice Experiment and requires Attention. But I am persuaded a judicious Ear will acknowledge the Effect. At any Rate the operation can do no Harm, and I believe the Idea is original. F. H.
RC (DLC). TJ’s entry in SJL under 10 June 1785, which reads: “received F. Hopkinson’s of Philada. Mar. 28.,” is undoubtedly an error for this of 20 Mch. (see TJ to Hopkinson, 6 July 1785). Enclosures: (1) Account of an experiment to improve the tone of the harpsichord (MS in MHi). (2) A copy of Hopkinson’s “New Sources of Amusement,” which had been printed in the Penna. Packet of 1 Mch. 1785 and is found in his Miscellaneous Essays, Philadelphia, 1792, ii, 138–45. Hopkinson’s remarks above seem to indicate that two essays were enclosed, but “New Sources of Amusement” includes both the Ewing-Rush and Bentley-Brown affairs.