Page:Journal of the Right Hon. Sir Joseph Banks.djvu/515

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ELECTRICITY
457

between the stopper and coating of lead; this probably did not condense the damp of the air so readily as glass, and consequently the machine worked well when mine refused to work at all.

Monday, 19th March 1770. The machine on being taken out of the box was found to have had the plate and one of the phials broken by some accident. The former was replaced by a spare one. Every part was perfectly dry and worked with great freedom, but a small proportion of electricity only could be excited, at most enough to strike through one card. During all our experiments the floor-cloth conducted as it had done before, though it had not been washed for some weeks. Our experiments were soon cut short by the wind, which was foul, freshening so much that we could not with safety let the machine stand. The day was rather hazy.

Friday, 23rd March 1770. All the day was clear, and the evening also very fine. At sunset the machine was set up. It at first entirely refused to work, but after about a quarter of an hour some sparks were excited. The most, however, that we could do was to obtain a slight shock. The floor-cloth conducted as usual, which we ascertained by resting upon a table or chair, in which case we did not feel the shock as we always did when standing upon the ground.