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price of beaver. Consider but a little, Conrad, and you must be of my opinion. If they meet so often to learn good things they would certainly have learned some before this time, but they are all ignorant. You know our practice. If a white man, in travelling through our country, enters one of our cabins we all treat him as I do you; we dry him if he is wet, we warm him if he is cold, and give him meat and drink that he may allay his thirst and hunger, and we spread soft furs for him to rest and sleep on-we demand nothing in return. But if I go into a white man's house at Albany and ask for victuals and drink, they say, 'where is your money ?' and if I have none, they say, ' get out you Indian dog. You see that they have not learned those little good things that we need no meetings to be instructed in, because our mothers taught them to us when we were children, and therefore it is impossible their meetings should be, as they say, for any such purpose or have any such effect; they are only to contrive the cheating of Indians in the price of beaver.''

We must with the slightest notice, pass over our philanthropist's services in founding the Pensylvanian Hospital ; his plans for cleaning, paving, and lighting the streets of Philadelphia, as well as his project for cleansing the streets of London; his appointment of Post-master General for America ; and also the honours of receiving the degree of Master of Arts from Harvard and Yale Colleges, in consideration of his improvements and discoveries in the electric branch of Natural Philosophy. He had already taken into partnership in the printing line, Mr. David Hall, who removed the onerous care of that business from his shoulders, and consequently he was enabled to apportion his time in other pursuits. Above all he entered with even more than his wonted eagerness into the department of plıysics already specified; for he declares that he never had been so wholly engrossed with any object of study before ; and that being willing to diffuse the information he obtained as fast as he made it his own, his house was for some time continually full of friends and acquaintances, crowding to witness the wonders of the new science.

ELECTRICAL EXPERIMENT. Franklin modestly dismisses his great attainments and discoveries of a philosophical nature in his personal narrative; and especially in relation to electricity, no single name was so largely connected with the science even in Europe as his. To cite the words of Dr. Priestley, he “bids

fair to be handed down to posterity, being equally expressive of the true principles of electricity, as the Newtonian philosophy is of the true system of nature in general.”

It was in 1746, that he entered with all the ardour and thirst for discovery which distinguished the philosophers of that day, upon a course of electrical experiment. This he was prompted and enabled to do, by means of certain apparatus which he had purchased from Dr. Spence, who was a lecturer on electricity. He was further tempted and encouraged in consequence of Mr. Peter Collinson, a gentleman of scientific attainments in London, having presented the Library Company at Philadelphia with a glass tube suited for the exhibition of electrical phenomena, at the same time communicating to Franklin some interesting intelligence of what had lately been done in this department of physical philosophy; and these circumstances were sufficient to excite the ardour of the American inquirer, who for about two years eagerly exercised himself in endeavouring to explore the hidden principles of electrical action. At length, about the year, 1747, he made the important discovery, that there are two kinds, conditions or affections of electricity, one of which he called the positive and the other the negative-and that it is by first disturbing the natural balance subsisting between these two states, and then restoring the equilibrium by bringing them into connexion, that an explosive effect is produced. In 1749 he first suggested his idea of explaining the phenomena of thunder gusts, and of the aurora borealis, upon electrical principles. He points out many particulars in which lightning and electricity agree; and he adduces many facts and reasonings cogent in support of his position. In the same year, he conceived the astonishingly bold and grand idea of ascertaining the truth of his doctrine, by actually drawing down the lightning with sharp-pointed rods raised into the region of the clouds. Even in this uncertain state, his passion to be useful to mankind, displays itself in a striking manner. Admitting the identity of electricity and lightning, and knowing the power of points in repelling bodies charged with electricity, and in conducting their fire silently and imperceptibly, he suggested the idea of securing houses, ships, &c., from being damaged by lightning, by erecting pointed rods that should rise some feet above the most elevated part, and descend some way into the ground, or water. The effect of these, he concluded, would be either to prevent a stroke by repelling the cloud beyond the striking distance, or by drawing off the electric fire which it contained ; or, if they could not

effect this they would at least conduct the electric matter to the earth, without any injury to the building.

It was not until the summer of 1758, that he was enabled to com. plete his grand discovery by experiment. The plan which he had originally proposed was to erect on some high tower or other elevated place, a sentry-box, from which should rise a pointed rod, insulated by being fixed in a small cake of resin. Electrified clouds passing, would, he conceived, impart to it a portion of their electricity, which would be rendered evident to the senses by sparks being emitted, when a key, the knuckle, or other conductor, was presented to it. Philadelphia at this time afforded no opportunity of trying an experiment of this kind. While Franklin was waiting for the erection of a spire, it occurred to him that he might have more ready access to the region of the clouds by means of a common kite. He prepared one by fastening two cross sticks to a silk handkerchief, which would not suffer so much from the rain as paper. To the upright stick was affixed an iron point; the string was as usual of hemp, except the lower end, which was silk. Where the hempen string terminated, a key was fastened. With this apparatus, on the appearance of a thunder-gust approaching, he went out on the common accompanied by his son, to whom alone ho communicated his intentions, well knowing the ridicule which too generally for the interests of science awaits unsuccessful experiments in philosophy. He placed himself under a shade to avoid the rain ; his kite was raised ; a thunder-cloud passed over it; no sign of electricity appeared. He almost despaired of success, when suddenly he observed the loose fibres of his string to move towards an erect position. He now presented his knuckle to the key, and received a strong spark. How exquisite must his sensations have been at this moment! On this experiment depended the fate of his theory. If he succeeded, his name would rank among those who had improved science; if he failed he must inevitably be subjected to the derision of mankind, or what is worse, their pity as a wellmeaning man, but a weak silly projector. The anxiety with which he looked for the result of his experiment may be conceived. Doubts and despair had began to prevail, when the fact was ascertained in so clear a manner that even the most incredulous could no longer withhold their assent. Repeated sparks were drawn from the key, a phial was charged, a shock given, and all the experiments made which are usually performed with electricity.

Franklin now wrote an account of his experiments and theories in the

success.

form of a letter to Mr. Collinson in England, who published them in a separate volume, under the title of“ New Experiments and Observations on Electricity, at Philadelphia, in America.” They were read with avidity, and met with the cordial approbation of many learned men in Great Britain, particularly of Dr. Priestley. But while Franklin's experiments and theories were received with delight by the learned in all quarters of the globe, they met at first with nothing but contemptuous sneers from the Royal Society of London. The French philosophers however thought very differently. An imperfect translation of the letters fell into the hands of the celebrated Buffon, who repeated the experiments with

Louis XV., hearing of these things was highly delighted with the repetition of such experiments, having been eager to witness them; nor did he fail to applaud the discoverer in flattering terms. Philosophers in other parts of Europe were thereby stimulated. Even the cold regions of Russia were penetrated by the ardour for discovery. Profes.. sor Richman of St. Petersburgh bade fair to add much to the stock of knowledge on the subject of electricity, when an unfortunate flash from his conductor put a period to his existence. “ The friends of science," says Dr. Stuber, Franklin's townsman and one of his biographers, whom we have been following in this account, “ will long remember with regret the amiable martyr to electricity."

By these experiments, Franklin's theory was established in the most convincing manner. When the truth of it could no longer be doubted, envy and vanity endeavoured to detract from its merit. That an American, an inhabitant of the obscure city of Philadelphia, the name of which was hardly known, should be able to make discoveries and to frame theories which had escaped the notice of the enlightend philosophers of Europe, was too mortifying to be admitted. However, at length the claims of the great experimenter and discoverer came to be universally acknowledged.

Besides the great principles thus brought to light, Franklin's letters on electricity contain a number of facts and hints which have contributed greatly towards reducing this branch of knowledge to a science. They have been translated into most European languages and into Latin. Apd in proportion as they have become known his principles have been adopted. În more recent times great advancement has been made in this field of inquiry. Still, Franklin's theory, as regards the practical benefit to be derived from employing lightning conductors, remains undisturbed.

The house, No. 141, High-street, Philadelphia, on the north side between Third and Fourth Streets, as we read in the " Annals” of that city, was originally the residence of the philosopher, and was the first house in the town which ever had a lightning rod affixed to it. This was put up by Franklin. The rod came into the bed-chamber in the second story on the gable-end, eastern side, and there, being cut off from its communication with the rod descending to the ground, the intermediate space, about one yard, was filled up with a range or chime of bells, which, whenever an electrical cloud passed over the place, was set ringe ing, throwing out sparks of electricity. These bells remained some time after Daniel Webster occupied the house, and were taken down to quiet the fears of his wife.

Franklin's labours in the department of physics, as indeed in every other branch or sphere, were all suggested by views of utility in the beginning, and were without exception applied to promote those views in the end. His letters upon electricity have been more extensively circulated than any of his other writings, and yet are entitled to more praise and popularity than they seem ever to have met with in England. Nothing can be more striking than the luminous and graphical precision with which the experiments are narrated, the ingenuity with which they were projected, and the sagacity with which the conclusion is inferred, limited, and confirmed.

The most remarkable thing, however, in these and indeed in the whole range of his physical speculations, is the unparalleled simplicity and facility with which the reader is conducted from one stage of the inquiry to another. The author never seems for a moment to labour or to be at a loss. The most ingenious and profound explanations are suggested as if they were the most natural and obvious way of accounting for the phenomena ; and Franklin appears to value himself so little on his most important discoveries, that it is necessary to compare him with others before you can form a just notion of his merits. As he seems to be conscious of no exertion, he feels no partiality for any branch of his speculations, and never seeks to raise the reader's idea of their importance by any arts of declamation or arrogance. Indeed, the habitual precision of his conceptions, and his invariable practice of referring to specific facts and observations, secured him in a great measure both from those extravagant conjectures in which so many inquirers have indulged, and from the zeal and enthusiasm which seems to be so readily engendered in their defence. He was by no means averse to

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