will prove impracticable? So far as I have consulted the savans of Paris, they have suggested no insurmountable difficulties. I have, however, quite as much confidence in your judg ment, from your valuable experience, as in that of any one I have met abroad. I think that you have pursued an original course of experiment, and discovered facts of more value to me than any that have been published abroad.

I will not trouble you at this time with my questions until I know your engagements. Accompanying this is a copy of a report, made by the Academy of Industry, of Paris, on my Telegraph, which I beg you to accept.

Believe me, dear Sir,

With the highest respect,

Your most obedient servant,
SAMUEL F. B. MORSE.

To PROFESSOR JOSEPH HENRY, Princeton.

To this letter I received the following reply:

:

PRINCETON, May 6th, 1839. DEAR SIR :-Your favor of the 24th ult. came to Princeton during my absence, which will account for the long delay of my answer. I am pleased to learn that you fully sanction the loan which I obtained from Dr. Gale, of your wire, and I shall be happy if any of the results are found to have a practical bearing on the Electrical Telegraph.

It will give me much pleasure to see you in Princeton after this week; my engagements will not then interfere with our communications on the subject of electricity. During this week I shall be almost constantly engaged with a friend in some scientific labors which we are prosecuting together.

I am acquainted with no fact which would lead me to suppose that the project of the Electro-Magnetic Telegraph is impracticable; on the contrary, I believe that science is now ripe for the application, and that there are no difficulties in the way, but such as ingenuity and enterprise may obviate. But what form of the apparatus, or what application of the power will prove best, can, I believe, be only determined by careful experiment. I can say, however, that so far as I am acquainted with the minutiae of your plan, I see no practical difficulty in the way of its application for comparatively short distances; but if the length of the wire between the stations be great, I think that some other modification will be found necessary, in order to develop a sufficient power at the farther end of the line. I shall, however, be happy to converse freely with you on these points when we meet. In the meatime I remain,

With much respect, yours, &c.,
JOSEPH HENRY.

To PROFESSOR MORSE.

Thus was prepared my first personal acquaintance with Prof. Henry. A few days after the receipt of this letter, I visited him, having prepared beforehand a few questions, the better to economize his time. The following is a copy of the original paper, (which I preserved,) with the answers of Prof. Henry, so far as they were given, put down by me in pencil at the time :

Questions prepared to ask Prof. Henry, and shown him in my visit May, 1839, and his answers, on reading them to him.

1st. Have you any reason to think that magnetism cannot be induced in soft iron, at the distance of 100 miles or more, by a single impulse, or from a single battery apparatus ? * "No."

2d. Suppose that a horse-shoe magnet of soft iron, of a given size, receive its maximum of magnetism by a given number of coils around it, of wire, or of ribbon, and by a given sized battery, or number of batteries, at a given distance from the battery, does a succession of magnets introduced into the circuit diminish the magnetism in each? "No."

3d. Have you ascertained the law which regulates the propor tion of quantity and intensity from the voltaic battery, necessary to overcome the resistance of the wire in long distances, in inducing magnetism in soft iron? "Ohm has determined it." 4th. Is it quantity or intensity which has most effect in inducing magnetism in soft iron? sity with long wires."

"Quantity with short, inten

According to the best of my recollection, I left New-York a few days after the receipt of his letter, in the morning of the day, and arrived at Princeton about noon, passed the afternoon and night with Prof. Henry, and returned to New-York the next morning. This was the first intercourse, either personal, or by correspondence, I ever had with him; and pausing a moment at this point, it may be well to inquire, how much of information I could have received from him personally or by correspondence, in the elaborating of my Telegraph as it then existed?

* That is, from any generator of the galvanic current, whether a voltaic, inductive, or thermo-electric apparatus.

From the autumn of the year 1829 till the autumn of the year 1832, I was in Europe, principally in Italy. Prof. Henry's paper in Silliman's Journal was published in 1831,* (in the interval of my absence from America.) I conceived the Telegraph on board the ship in 1832, while on my return home, essentially as it now exists. It was operated in my rooms before numerous persons, my pupils, and others, in 1835; it was exhibited to a large audience of a thousand or more persons, through ten miles of wire, in the New-York City University, in the autumn of 1837; to a committee of the Franklin Institute in Philadelphia, in January, 1838; to Congress and the Cabinet at Washington, for three months, in the early part of that year; to the Academy of Sciences, and thousands of visitors in Paris, in the autumn of 1838; to Members of the Royal Society, of both Houses of Parliament, and the Lords of the Admiralty at Lord Lincoln's,† in London, in the month of March, 1839; and after all this, I first became acquainted, either personally, or by correspondence, with Prof. Henry.

Here then is a controlling date, (1839,) proved to be most incorrectly deposed to by Prof. Henry (as 1837). It is a date which controls the question of fact, whether I could have derived from him any information directly by personal interview, or correspondence with him, leaving but two other sources from which aid from him could be derived by me in the elaboration of my Telegraph.

There are but three sources whence I could derive scientific information from Professor Henry.

1st. Directly by personal interview, or by correspondence. 2d. Indirectly through others.

3d. From his published works.

The first, I think, is effectually disposed of. The other sources will be examined in the sequel.

While on the subject of erroneous dates given in the deposi

* Before examining this paper, let me for a moment grant, for argument's sake, that it is (what some would claim for it) suggestive of my Electro-Magnetic Telegraph, what are the probabilities that it could reach me in Italy or France, where I was then residing, so as to influence my mind in the conception and construction of the Telegraph on my return voyage in 1832? The probabilities, it will be seen, are certainly very small. The fact is, it did not come to my knowledge until five years after my return, (in 1837.)

†The present Duke of Newcastle.

tion, I proceed to notice others, illustrative of the incapacity of Prof. Henry, from defective memory, to depose correctly where dates are essential to elicit the truth.

In connection with his declaration that, in 1837, he became acquainted with me in New-York, (instead of 1839 in Princeton,) he says that he "gave me a certificate in the form of a letter.” I give the certificate letter thus referred to, and its date, referring the reader to his deposition, answer to 4th interrogatory, for his narration on this point.

"PRINCETON COLLEGE, Feb. 24th, 1842. "MY DEAR SIR:-I am pleased to learn that you have again petitioned Congress, in reference to your Telegraph, and I most sincerely hope you will succeed in convincing our Representatives of the importance of the invention. In this you may, perhaps, find some difficulty, since, in the minds of many, the Electro-Magnetic Telegraph is associated with the various chimerical projects constantly presented to the public, and particularly with the schemes, so popular a year or two ago, for the application of electricity as a moving power in the arts. I have asserted from the first, that all attempts of this kind are premature, and made without a proper knowledge of scientific principles. The case is, however, entirely different in regard to the Electro-Magnetic Telegraph. Science is now fully ripe for this application, and I have not the least doubt, if proper means be afforded, of the perfect success of the invention.

"The idea of transmitting intelligence to a distance, by means of electrical action, has been suggested by various persons, from the time of Franklin to the present; but until within the last few years, or since the principal discoveries in electromagnetism, all attempts to reduce it to practice were necessarily unsuccessful. The mere suggestion, however, of a scheme of this kind, is a matter for which little credit can be claimed, since it is one which would naturally arise in the mind of almost any person familiar with the phenomena of electricity; but the bringing it forward at the proper moment, when the developments of science are able to furnish the means of certain success, and the devising a plan for carrying it into practical operation, are the grounds of a just claim to scientific reputation as well as to public patronage.

About the same time with yourself, Prof. Wheatstone, of London, and Dr. Steinheil, of Germany, proposed plans of the Electro-Magnetic Telegraph; but these differ as much from yours as the nature of the common principle would well permit; and unless some essential improvements have lately been made

in these European plans, I should prefer the one invented by yourself.

"With my best wishes for your success, I remain, with much esteem, Yours truly,

(Signed)

"PROFESSOR MORSE."

"JOSEPH HENRY.

It will be perceived that Prof. Henry has misrecollected the time and circumstances of our first acquaintance, making the date 1837, in New-York, instead of 1839, in Princeton, and he leaves the impression that the time of giving me his "certificate" letter was in 1837, instead of 1842, the true date, as the letter itself shows.

But while on this topic I may as well fix certain other dates which have a bearing on Prof. Henry's qualifications for a deponent. Prof. Gale, my colleague, left the University for the South in the spring of 1839. Prof. Draper had been appointed his successor in the Chair of Chemistry in September, 1838; but, being unable at once to enter upon the duties of his office, Prof. James C. Fisher received a temporary appointment in January or February of 1839. On my return from Europe, in April, 1839, I found Mr. Fisher in the University, and then made my first acquaintance with him. I had never seen or known him previously. The bill before Congress making an appropriation to test the practicability and utility of my Telegraph, passed on the 3d of March, 1843. My scientific assistants, in preparing the Telegraph, could not well have been appointed previous to the passage of this bill. Prof. Gale, Prof. Fisher, and Mr. Vail received their appointment from me, as my assistants, March 27, 1843; and they were confirmed by the Secretary of the Treasury March 28, 1843. The records of the Treasury Department will verify these dates. Let Prof. Henry's narrative now be compared with these facts. He says:-"I learned in 1837, or thereabouts, that Prof. Gale and Dr. Fisher were the scientific assistants of Mr. Morse in preparing the Telegraph. Mr. Vail was also employed, but I know not in what capacity, and I am not personally acquainted with him." Is not here further proof of Professor Henry's incorrectness in giving dates, and looseness and inaccuracy of historical narration?