Science Siftings

New Zealand Tablet, Volume LII, Issue 6, 11 February 1925, Page 62

Science Siftings

By “Volt”

The Lightning-Rod's Inventor

It is to Benjamin Franklin, the great American scientist, that the credit beolngs of inventing the first lightning conductor (says a writer in John o' London's Weekly). In 1747 a London scientist, Peter Collinson, presented to the Philadelphia Library a glass tube of the kind then used for producing electricity by rubbing with silk or skin. Franklin was delighted with this, and became so engrossed in experimenting with it that he declared he had little leisure for anything else.

With him collaborated three other pioneers —Kinnersley, Hopkinson, and Syng. Between them, within six months, they found out the power of metal spikes to throw off "electrical points," as they called them; 'they mven r A an electrical machine, better fitted than uioe-rub'b'ng I'oi throwing off. the electric spar's; and they discovered what is now known as positive and negative electricity. Then Franklin began his attempt to identify lightning with the electric spark produced by mechanical means.

All these discoveries and experiments Franklin reported by letter to Collinson, who laid the letters before the Royal Society in London. When these learned men laughed at them in derision, Coliinson persuaded the editor of the Gentleman's Magazine to issue a little book on the subject, which was published in 1751. This had such a vogue that it was translated into French, German, Latin, and Italian.

The first actual experiment was made by the scientist D'Alibard, on May 10, 1732. On top of a hill he raised a rod, 99 feet high, and "a thunderbolt having passed over the place where the bar stood, those who were appointed to observe it drew near and attracted from its sparks of fire, the same kind of commotion as in the common electrical experiment."

Franklin himself did not at first put his invention to any practical test. He thought a hill of some height was necessary for the purpose, and this was not to be had in Philadelphia. When he did put it to practical proof he used neither a steeple (his own original suggestion), nor even an iron rod, but a specially made kite.

George 111 disliked Franklin's political opinions, and was anxious to discredit his scientific discoveries as well. He therefore ordered the lightning conductors on Kew Place to have blunt instead of pointed ends. When he asked Sir John Pringle, then president of the Royal Society, what he thought of the change, Sir John told him plainly that "the laws of Nature are not changeable at the royal pleasure." This annoyed his Majesty so much that he suggested Sir John had better resign his presidency of the Royal Society. He did so, and the breach between them was never'healed. "Sides" were taken over the quarrel, the Court naturally supporting the King, while the wits sympathised with Sir John.

Next World War: Application of Chemistry. A cable message from Washington to the daily press, under date February 1, says; Mr. C. D. Wilbur (Secretary of the Navy) has issued a statement in regard to the ridiculous stories appearing in the press, magazines, and books from time to time, predicting the horrors of the next great war. Mr. Wilbur says: “The writers who seek to terrorise the people of the world regarding the awful calamities of the next war overlook one fundamental principle of war namely, that to have one you must have defence, and that the method of defence should be commensurate with the offence. Thus if poison gas is used by one side it can , be used by the other. If disease germs are used by one side they can be employed by the other, and the nation, moreover, using disease germs cannot confine the effects of disease to one side of the fighting line:” Mr. Wilbur stresses the negotiations of treaties prohibiting the use of gas, and says, moreover, that it is impossible to transport or apply sufficient poison gas or other chemicals, or biological products to poison the populations of whole cities or countries as the writerssome of them scientists —predict. The idea is ridiculous, nor should it even be relegated to the field of bedtime stories. “My own judgment,” says Mr. Wilbur in conclusion, “is that the next war will be like most wars in history, sporadic and local, involving comparatively few peopi|, and will be quickly over. The chances are' that the judgment of mankind will oppose any war for the whole purpose of the extermination or annihilation of nations or peoples. Ape Farm for Science. The Pasteur Institute (says the London Times ) has set up in the island of Los, near Konakri, in French Guinea, a “farm” for the breeding and preservation of apes and monkeys required for medical experimental purposes. This is a large, well-watered, woody, and fertile tract of land near a forest inhabited by chimpanzees and several species of monkeys. A director has been appointed,- and the necessary outbuildings ’ constructed. These include accommodation for sick animals. The Tropical Diseases Bulletin remarks that himpanzees are the “most suitable of our relatives for pathological study.” ' They are also capable of affording material for experimental psychology. The baboons are far less easily managed, but very intelligent. There are many human diseases, including measles, scarlatina, typhus, . yellow fever, and influenza, which cannot be transmitted to ordinary experimental animals (rabbits, - guinea-pigs, etc.). The study of these m|sfi. be abandoned altogether unless the relatives” of man can be’ utilised. Thus the effort of the Pasteur Institute is likely to lead to important results.