Art. XXIV. Extract of a Letter from Colonel Gibbs to the Editor.
Art. XXIV. Extract of a Letter from Colonel Gibbs to the Editor.
Sunswick, June, 1818.
Dear Sir,
Since I saw you, I have made only one experiment on magnetism. I determined the power of my magnet, as it had been shut up in the dark for a long time, and lying down. I then exposed it to the rays of the sun, also lying down, and remote from the iron support, and I found that it had gained 12 oz. power in 40 minutes, and 14 oz. power only in five hours.