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In August, 1772, a committee of the Royal Society, under the direction of the government, examined the powder magazines at Purfleet, for the purpose of suggesting some method of protecting them from lightning. Dr. Franklin had already visited Purfleet, at the request of the Board of Ordnance, and recommended the use of pointed iron rods, according to the method originally proposed by him, which had been practised with success in America for more than twenty years. The committee consisted of Messrs. Cavendish, Watson, Franklin, Wilson, and Robertson, all of whom were distinguished for their acquaintance with electricity. A Report was drawn up by Dr. Franklin, and signed by the committee, in which they advised the erecting of pointed rods, with a minute description of the manner of constructing them.
Mr. Wilson was the only dissenting member, who gave it as his opinion, that pointed conductors were dangerous, inasmuch as they attracted the lightning, and might thus overcharge the rod and promote the mischief they were intended to prevent. According to his theory, the conductors ought to be blunt at the top. To satisfy himself more fully in this particular, as well as to remove all doubts from the minds of others, Dr. Franklin performed a series of new electrical experiments, by which he demonstrated, that pointed rods are preferable to blunt ones. It is true, they invite the lightning, yet this is the very thing desired, for the charge is thereby silently and gradually drawn from the clouds, and conveyed without
to see you at Oxford, and that you look so well." The conversation continued for a short time. Alluding to this incident, Dr. Franklin said, "Of all the men I ever met with, he is surely the most unequal in his treatment of people, the most insincere, and the most wrongheaded." It is believed, that there was no intercourse afterwards between them.
danger to the earth; whereas a conductor, blunt at the top, may receive a larger quantity of the fluid at once, than can be carried away, which will thus cause an explosion. This was the principle, upon which his theory of lightning-rods was originally formed, and it was established more firmly than ever by these new experiments. They were satisfactory to nearly all the men of science, and the conductors at Purfleet were erected in the manner recommended by the committee. *
The controversy about pointed and blunt conductors continued for some time. Mr. Wilson grew warm in it, and gained adherents to his cause. A stroke of lightning fell upon the buildings at Purfleet in May, 1777, without doing any damage, but this accident brought the subject again into agitation. It was referred to another committee of the Royal Society, who reported as before in favor of pointed rods. Mr. Wilson seized this occasion to propagate his theory with renewed vigor, repeating his experiments in public, and in presence of the King and royal family, by whom they were countenanced. At one of these exhibitions Lord Mahon was present, and showed by experiments of his own, that Mr. Wilson misunderstood the theory of Dr. Franklin, or represented it unfairly. Mr. Henly and Mr. Nairne also demonstrated the fallacy of his principles. In the midst of the dispute, however, the pointed conductors were taken down from the Queen's palace, and blunt ones were substituted in their place. Dr. Ingenhousz, a member of the Royal Society, wrote an account of the affair, inveighing against Mr. Wilson's conduct, which was transmitted to a gentleman in Paris, with a request that he would show it to Dr. Franklin and have it published in France. Dr. Franklin replied as follows to this gentleman, in a letter dated at Passy, October 14th, 1777.
"I am much obliged by your communication of the letter from England. I am of your opinion, that it is not proper for publication here. Our friend's expressions concerning Mr. Wilson will be thought too angry to be made use of by one philosopher when speaking of another, and on a philosophical question. He seems as much heated about this one point, as the Jansenists and Molinists were about the five. As to my writing any thing on the subject, which you seem to desire, I think it not necessary, especially as I have nothing to add to what I have already said upon it in a paper read to the committee, who ordered the conductors at Purfleet; which paper is printed in the last French edition of my writings.
"I have never entered into any controversy in defence of my philo
The successor of Lord Hillsborough in the American department was Lord Dartmouth. This appointment gave satisfaction to the colonial agents, and it has even been supposed, that Dr. Franklin was instrumental in effecting it. Some time before Lord Hillsborough's resignation, it was rumored, that he would probably be removed, as he was known not to be on cordial terms with the ministry; and, when Dr. Franklin was asked by a friend at court, if he could name another person for the place, who would be more acceptable to the Americans, he answered, "Yes, there is Lord Dartmouth; we liked him very well when he was at the head of the Board formerly, and probably should like him again." The colonists generally were pleased with the change. Lord Dartmouth had been on their side in opposing the Stamp Act,
sophical opinions; I leave them to take their chance in the world. If they are right, truth and experience will support them; if wrong, they ought to be refuted and rejected. Disputes are apt to sour one's temper, and disturb one's quiet. I have no private interest in the reception of my inventions by the world, having never made, nor proposed to make, the least profit by any of them. The King's changing his pointed conductors for blunt ones is, therefore, a matter of small importance to me. If I had a wish about it, it would be, that he had rejected them altogether as ineffectual. For it is only since he thought himself and family safe from the thunder of Heaven, that he dared to use his own thunder in destroying his innocent subjects."
The wits entered the lists and amused the public and themselves at the expense of the philosophers. In allusion to this dispute, and to the political state of the times, the following epigram was written.
"While you, great GEORGE, for safety hunt,
The empire 's out of joint.
Franklin a wiser course pursues,
And all your thunder fearless views,
By keeping to the point."
The controversy died away, and was not revived so as to diminish the confidence in Franklin's theory of pointed conductors, which has been universally followed in practice.
and they hoped much from his character, and the dispositions he had shown towards them.
If they were disappointed in this hope, it was perhaps less owing to the fault of this minister, than to the policy which had been adopted in regard to America, and which he was obliged to support while he retained his office. In the administration of his own department, he at first assumed some degree of independence, and his conduct was more mild and considerate, than that of his predecessor; but he soon betrayed a want of consistency and firmness, which, although he was inclined to good measures, led him to join in sustaining the worst. He abolished the rule of not admitting agents to appear before the Board of Trade, whose election had not been approved by the governors, and restored to them all their former privileges. He consulted them frequently, and in a temper which at least evinced a desire to become thoroughly acquainted with the grounds of the colonial complaints, whatever may have been his opinion as to the expediency or the manner of removing them.
At his first interview with Lord Dartmouth on business, Dr. Franklin put into his hands a petition from the Assembly of Massachusetts to the King. Hutchinson, the Governor of the province, had lately received his salary from the crown, contrary to all former usage, and, as the Assembly declared, contrary to the spirit and intent of their charter, and to the constitution under which the government was established. It was a violation of their rights, and an alarming precedent, out of which might spring innumerable abuses subversive of their liberties. It was a prerogative of the Assembly, which had never before been encroached upon or questioned, to tax the people by laws of their own enacting for the support of government; and
this was designed not more as a security for the existence of government, than as a protection from any undue influence of the crown over the officers by whom it was administered. The Governor could negative their laws, and, being appointed by the King, the only tie that bound him to their interests was his dependence on them for his means of support. When this tie was broken, by making him exclusively dependent on the crown for his office and his salary, no motive remained with him for cultivating the good will of the people, and no restraint which would prevent him from exercising his power, whenever he should think proper, in such a manner as to undermine and ultimately break down the pillars of the constitution. The Assembly of Massachusetts saw, in this dangerous innovation, the ruin of their freedom, if it should be allowed to grow into a practice. They passed several spirited resolves in opposition to it, and petitioned the King for redress.
It was this petition, which Dr. Franklin handed to Lord Dartmouth. When they met again to discourse upon the subject, his Lordship advised, that it should not be presented for the present; said he was sure it would give offence; that it would probably be referred to the judges and lawyers for their opinion, who would report against it; and that the King might possibly lay it before Parliament, which would bring down the censure of both Houses in the shape of a reprimand by order of his Majesty. This would irritate the people, and add fresh fuel to the heats, which had already become so violent as to threaten unhappy consequences. He believed it would be better for both parties, if a little time could be left for these heats to cool; yet, as the petition had been delivered to him officially, he would, if Dr. Franklin insisted,