At the same time that this meeting of the American Association was being held at Philadelphia, where we were treated with marvelous hospitality,--excursions, soirées, dinners, parties, etc., etc.--and as though it were not quite sufficient to bring over humble Britishers from this side of the Atlantic to suffer the intense heat at one meeting of the Association, they held at the same time an Electrical Conference. There was a conference of electricians appointed by the United States Government, that was chiefly distinguished on the part of the American Government by selecting those who were not electricians. But many attended the Electrical Conference who stand high as electricians, one especially, who, though perhaps from want of experience he did not shine very brilliantly as a chairman, certainly stands as one of the ablest electricians of the day--I mean Professor Rowland. The Conference was held under Professor Rowland's presidency, and nearly all the well-known professors of the United States attended. The Conference was established by the United States Government to take into consideration the results and conclusions arrived at by the Congress of 1884, held in Paris. The Paris Congress decided upon adopting certain units of resistance of electromotive force, of current, and of quantity, and they determined the particular length of a column of mercury that should represent the ohm--a column of mercury 106 centimeters long and of one square millimeter in section. It was necessary that the United States should join this Conference, so a commission was appointed to consider the whole matter. All these units were brought before them, as well as the other conclusions of the Paris Congress, such as the proper mode of recording earth currents and atmospheric electricity. The Paris units were adopted in face of the fact that the length determined upon at Paris was not the length that Professor Rowland himself had found as that which should represent the ohm. It differed by about 0.2, as near as I can remember; but it was thought so necessary that uniformity and unanimity should exist all over the world in the adoption of a proper unit, that all differences were laid aside, and the Americans agreed to comply with the resolutions of the Paris Congress.