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it. Moved by that irrepressible impulse which is a mark of genius, he purchased in Europe the rough disks of optical glass necessary to make small telescopes. Having succeeded in making one of four inches aperture to his satisfaction, the problem was to make his skill known to astronomers. I regret to say that he found this a very difficult part of his task. The director of the Harvard Observatory would not believe that Mr. Clark could make a really good telescope. When the optician took his first instrument up to the observatory to be tested, the astronomer called his attention to the fact that it showed a little tail attached to the star, which, of course, had no real existence, and was supposed to arise from a serious defect in the figure of the glass. Mr. Clark saw it, but was sure it had not been there before. He could not explain it at the time, but afterwards found that it was caused by the unequal temperature of the air in the tube of the telescope when it was exposed under the sky at night.

Unable to secure any effective recognition at home, he determined to try abroad. He made a larger instrument, scanned the heavens with it and discovered several close and difficult double stars. He wrote out descriptions of these objects and sent them to Rev. W. R. Dawes, an amateur astronomer in England, devoted to this branch of the science. Mr. Dawes was a lovely character. He looked at the objects described by Clark and found great difficulty in making them out. Yet the descriptions were so accurate that it was evident to him that Mr. Clark's instrument must be of the highest class.