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alleged facts, other than unwarranted inference from an experiment by Prof. Henry, exhibiting a result not verified by experiment or experience, before or since. Of that we shall say more hereafter.

At page 13, Mr. Chase says, "Morse was unacquainted with electricity and electro magnetism."

It is in evidence that he attended a series of lectures on electricity and electro magnetism delivered by Prof. Dana in 1827 during which one of Sturgeon's Electro Magnets was exhibited. That identical Electro Magnet, as well as the original manuscript of Dana's Lectures, hunted up through Morse's recollection of that science as then explained by the learned Lecturer, were in evidence; but the mysterious fire in the Clerk's Office has disposed of those lectures, though the Electro Magnet is still in Court.*

At page 26 Mr. Chase says the decision of Judges Grier and Kane in Philadelphia amounts to this, that Morse was the "proprietor of the electric current for telegraphic purposes and that without discovering any new principle whatever."

There is no warrant for such a broad assertion either in that decision or in Morse's claims. They do not touch Wheatstone's nor any other, except marking telegraphs.

Page 43, Mr. Chase says "I pass, barely mentioning it here, Prof. Henry's contrivance for breaking and closing a second circuit used in 1833 or 1834, which left nothing new in point of principle to be invented by Morse or any body else for extending telegraph circuits." Nobody testifies to such use in 1833 or 1834. Henry himself, so far from testifying to any use at any time, is not certain that he explained it to his class before he went to Europe in 1837, and does not say that he ever did it afterwards.

Now let us see what had been done before Morse took up the subject, and in this we shall, in all sincerity, attempt to mete out exact justice to every one whom it is necessary to mention. Electricity, Galvanism, sundry modes of generating them, the circuit, and modes of breaking and closing it, were known.

Oersted in 1819 discovered that the electric current, passing on the Circuit wire, would deflect a magnetic needle brought in proximity to it. This was the discovery of Electro Magnetism; a mechanical effect was then produced.

Schweiger conceived, that if the current could be made to pass several times around the needle, the mechanical effect would be increased. With insulated wire he made a coil of many turns in a shape somewhat elliptical, which he embraced in the Circuit and suspended the Magnetic needle within it. A spe

There is another mystery in the non appearance upon the Record of a deposition of Prof. Silliman, touching this matter.

cimen of this contrivance has been exhibited to the Court, and it is called Schweiger's Multiplier. The result was as he expected. Arago discovered that the Electric Current passing upon a wire would attract iron filings.

Sturgeon conceived, that if a part of the Circuit wire were made to pass several times around a piece of iron, the same influence which moved the needle and iron filings, would produce Magnetism in the iron. Ile insulated a piece of iron rod, coiled the circuit wire spirally around it, and on applying the current, found that the iron became Magnetic. This was the invention of the Electro Magnet.

It occurred to Prof. Henry, that by applying Schweiger's Multiplier to Sturgeon's iron bar, a much more powerful Magnet might be produced. He tried the experiment and succeeded. By multiplying the turns of wire around the iron, it was found that the Magnetism was increased somewhat in proportion to the number of turns added, so that mechanical effects could be produced at greater distances on the electric circuit than with the Magnet as arranged by Sturgeon.

Henry did not invent the Multiplier, nor the Electro Magnet. His merit so far as the Electro Magnet is concerned, consists in combining together the inventions of two other men, and producing a more powerful mechanical action. He does not in his article published in Silliman's Journal in January, 1831, claim to have discovered any new principle in respect to the Electro Magnet; It is entitled "On the application of the principle of the galvanic Multiplier to Electro Magnetic apparatus, and also to the development of great Magnetic power in soft iron with a small galvanic element," meaning small battery.

The application of known principles in such manner as to produce an improved result, was all he claimed.

If O'Reilly and his associates had an interest in depreciating Prof. Henry's experiments, they could doubtless employ Counsel to say as has been said of Morse's invention, that this combination of Schweiger's Multiplier, with Sturgeon's Electro Magnet was "a very simple contrivance"-one so obvious and natural, that it might have occurred to anybody, and must "inevitably" have soon occurred to somebody. Neverthelessit was an important accession to the mass of material out of which a telegraph was to be constructed.

But Prof. Henry, as he says himself, was not in pursuit of a Telegraph, or any other particular practical result useful to society. Having made his improvement, he threw it into the mass furnished by Oersted, Schweiger, Arago, Sturgeon &c., to be employed by anybody else who had the inclination to make it useful to his fellow-men. Henry's experiments were made with little more than one-fifth of a mile of wire, and although

they conclusively showed that mechanical action could be produced by means of his improvement at greater distances from the battery than was before possible, they by no means showed that it could be produced at the distance of 100, 20, or even ten miles, and especially they did not show that it could be produced with a sufficient force, to mark or indent paper.

After what has been said, written and printed, on the other side, it may surprise the Court to learn, that it was not his improvement in the Electro magnet, which Prof. Henry said in his article of 1831 was "directly applicable to Mr. Barlow's project of forming an Electro-Magnetic Telegraph," but it was the result of an experiment to ascertain the effect of currents from batteries of different descriptions, a result apparently inconsistent with all experiment and experience before and since, but in which at the time Prof. Henry seems to have had great confidence.

To place this matter in an unquestionable light, we quote the entire passage which relates to it in Henry's article in the 19th volume of Silliman's Journal, page 403, it being in evidence in this case, viz:

"Experiment 7. The whole length of the wire [over onefifth of a mile] was attached to a small trough on Mr. Cruikshank's plan, [a battery] consisting of 25 double plates, and presenting exactly the same extent of zinc surface to the action of the acid as the battery used in the last experiment. The weight lifted in this case was 8 oz. When the intervening wire was removed and the trough attached directly to the ends of the wire surrounding the horse shoe, it lifted only 7 oz. From this experiment it appears, that the current from a galvanic trough is capable of producing greater Magnetic effect on soft iron after traversing more than one-fifth of a mile of intervening wire, than when it passes only through the wire surrounding the Magnet. It is possible that the different states of the trough with respect to dryness, may have exerted some influence on this remarkable result, but that the effect of a current from a trough, if not increased, is but slightly diminished in passing through a long wire, is certain. A number of other experiments would have been made to verify this, had not our use of the room been limited, by its being required for public exercises.

"On a little consideration, however, the above result does not appear so extraordinary as at the first sight, since a current from a trough, possesses more projectile force, to use Prof. Hare's expression, and approximates somewhat in intensity to the electricity from the common machine.

"May it not also be a fact that the galvanic fluid, in order to produce the greatest magnetic effect, should move with a small velocity, and that in pasing through one-fifth of a mile, its velo

city is so retarded as to produce a greater magnetic action? But be this as it may, the fact that the magnetic action of a current from a trough is at least not sensibly diminished by passing through a long line directly, is applicable to Mr. Barlow's projent of forming an Electro-Magnetic Telegraph, and also of material consequence in the construction of the galvanic coil."

"From this experiment,' says Prof. Henry, 'it appears that a current from a galvanic trough, is capable of producing greater magnetic effect on soft iron after traversing more than one-fifth of a mile of intervening wire, than when it passes only through the wire surrounding the magnet."

After attempting to account for a result so extraordinary and apparently so absurd, he adds, "but be this as it may, the fact that the magnetic action of a current from a trough is, at least, not sensibly diminished by passing through a long wire, is directly applicable to Mr. Barlow's project of forming an Electro-Magnetic Telegraph, &c."

Had this result been verified by subsequent experiment or experience, it would have saved Prof. Morse the necessity of inventing combined and local circuits, and Receiving magnets with all their delicate adjustments. And it would be a day of joy and rejoicing among Telegraphers throughout the Union, if Prof. Henry were now able to come forward with his Telegraph of a Single Circuit, the longer the better, running through their Register magnets, and saving the perpetual adjustment of Receiving magnets arising from the feebleness and variableness of the currents, though great improvements have been made in batteries since 1831; it would form a new era, not less distinguished than that which witnessed the introduction of the more complicated system of Prof. Morse. Unfortunately the result of this experiment turned out to be utterly delusive. The deductions of Barlow and others from previous experiments, that the magnetic force of the current diminishes somewhat in proportion to the increased length of the Circuit, became an established fact, as it is an established law of nature, and Henry's improved Electro magnet, like Sturgeon's original magnet, and the magnetic needles used by other experimenters, came under the dominion of that law, no matter what kind of battery was used, though some kinds are better than others.

These facts and circumstances show, that Prof. Henry's idea of an Electro-Magnetic Telegraph in 1831 was a telegraph of a single circuit based on the fallacious conclusion, that he had discovered means by which the magnetic action could be made greater with the same battery on a long Circuit than on a short one, or "at least" to use his own emphasized expression "is not sensibly diminished by passing through along wire." If this were a fact, there would be no need of combined circuits to renew the

exhausted power of the electric current. They would be but a worse than useless complication. There is, however, not the shadow of such a combination in Henry's Article of 1831, nor is it probable that then, or for a long time afterwards, his mind was directed to the means of removing an obstacle which he did not suppose to exist, particularly as his object was not to invent a Telegraph but to develope general science.

In another point of view, however, Prof. Henry's experiments were of importance. They confirmed the discovery previously made by Prof. Hare, that a current from "a trough" or from two or more plates, as in his 20th experiment, produces more magnetism in a long circuit, than a current from one plate presenting the same given surface to the acid. That the discovery was not original with Prof. Henry, is shown by his article in Silliman's Journal in which he distinctly concedes it to Prof. Hare, in his account of both his 7th and 20th experiments. Yet, Prof. Henry's experiments confirmed the discovery, and though he did not himself apply it to any useful purpose, he prepared it, so to speak, for practical application by others. It must not be forgotten, however, that this current from this kind of battery, now called a battery of intensity, though it produces more magnetism in long circuits than a battery of one pair of plates now called a battery of quantity, yet both are subject to the same law of reduction of their own magnetic influence, as the length of the circuit is increased.

It must be noted, that when Prof. Henry speaks of "mechanical action" produced by Electro Magnetism, he means any motion however feeble, such as the motion of the magnetic needle and the motion of the bar in Morse's Receiving magnet. Such "mechanical action" is wholly insufficient for Morse's purposes, and was useless to him without means to produce a much greater force.

It must also be noted, that the title "Electro-Magnetic Telegraph" is a general name, not confined to Morse's Telegraph, but comprehending Wheatstone's needle Telegraph, and all other Telegraphs of which Electro Magnetism constitutes the principal Agent. A force sufficient to vibrate Wheatstone's needles would be wholly inadequate to give an efficient impulse to Morse's pen. It does not follow, that when Prof. Henry or others speak of "the Electro-Magnetic Telegraph," they mean Morse's marking Telegraph. One kind may be practicable by an amount of magnetic force which would be wholly inadequate to give vitality to another. And of all known kinds, Morse's Telegraph requires the greatest magnetic force.

The Counsel on the other side have confounded all kinds of magnetic telegraphs together, by which expedient they give a meaning to some of the testimony which was never intended.

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