In 1871 he came to New York, and having attracted the attention of the Stock Exchange by some ingenious suggestions put forth while busied in repairing the machine that recorded quotations, he was made Superintendent of the Gold and Stock Company, and brought out his invention of the printing-telegraph, by which the fluctuations of the stock-market in any part of the country are instantly recorded on narrow strips of paper. [Illustration: Thomas A. Edison--The Wizard of Menlo Park.] The immediate success of this invention, and the great demand for the machines, led him to establish a workshop for their manufacture in Newark, N. J. But soon the need of still more space, and the desire for freedom from interruption while at his work, obliged him to give up Newark, and he found new quarters at Menlo Park, N. J.--a bare plot of barren acres destitute of natural attraction of any kind, unless it be--what to Edison indeed is a great charm--an uninterrupted view of the sky; a place virtually unknown before he planted there the rude buildings that house his wonderful inventions; yet now a place known to scientific men all over the world; the Mecca of many a mind seeking to wrest from Nature her dearest secrets. No doubt, many of the inventions that have made Edison famous must be ascribed in their conception and ripening' to various periods of his life, but to the popular mind they are all associated with the wizard's present home, from whence for several years the bulletins of inventions--playful, useful, necessary, revolutionary--often as simple in their mechanism as they are astonishing in their results, have been given to a delighted world. Some of Edison's inventions have a character at present of little more than picturesque playfulness, such as the Phonograph, perhaps the most remarkable of these minor inventions; the Aerophone, by which sounds are amplified without loss of distinctness; the Megaphone, an instrument which, inserted in the ear, so magnifies sounds that faint whispers may be heard a thousand feet; the Phonometer, for measuring the force of the soundwaves caused by the human voice; the Microtasimeter, for measuring small variations in temperature. This has been tested for so small a variation as 1/24000 of a degree Fahrenheit, and in 1878 was used to detect the presence of heat in the sun's corona. The most familiar of these lesser inventions is the Phonograph by which sounds are made self-recording and capable of being repeated. While this curious invention--almost childish in its simplicity--is as yet little more than a plaything, and has proved of small utility, it makes, nevertheless, a strong appeal to the imagination when we reflect that by its aid the voice of any human being may be transmitted to ages far in the future, and its living tones be heard long after he who uttered them has returned to the dust.