'To some she is the goddess great; To some the milch-cow of the field; Their business is to calculate The butter she will yield.' The institution has proved a remarkable success. From it has emanated a series of marvellous inventions which have carried the name of Edison throughout the whole civilised world. Expense was disregarded in making the laboratory as efficient as possible; the very best equipment was provided, the ablest assistants employed, and the profit has been immense. Edison is a millionaire; the royalties from his patents alone are said to equal the salary of a Prime Minister. Although Edison was the master spirit of the band, it must not be forgotten that his assistants were sometimes co-inventors with himself. No doubt he often supplied the germinal ideas, while his assistants only carried them out. But occasionally the suggestion was nothing more than this: 'I want something that will do so-and-so. I believe it will be a good thing, and can be done.' The assistant was on his mettle, and either failed or triumphed. The results of the experiments and researches were all chronicled in a book, for the new facts, if not then required, might become serviceable at a future time. If a rare material was wanted, it was procured at any cost. With such facilities, an invention is rapidly matured. Sometimes the idea was conceived in the morning, and a working model was constructed by the evening. One day, we are told, a discovery was made at 4 P.M., and Edison telegraphed it to his patent agent, who immediately drew up the specification, and at nine o'clock next morning cabled it to London. Before the inventor was out of bed, he received an intimation that his patent had been already deposited in the British Patent Office. Of course, the difference of time was in his favour. When Edison arrived at the laboratory in the morning, he read his letters, and then overlooked his employees, witnessing their results and offering his suggestions; but it often happened that he became totally engrossed with one experiment or invention. His work was frequently interrupted by curious visitors, who wished to see the laboratory and the man. Although he had chosen that out-of-the-way place to avoid disturbance, they were never denied: and he often took a pleasure in showing his models, or explaining the work on which he was engaged. There was no affectation of mystery, no attempt at keeping his experiments a secret. Even the laboratory notes were open to inspection. Menlo Park became a kind of Mecca to the scientific pilgrim; the newspapers and magazines despatched reporters to the scene; excursion parties came by rail, and country farmers in their buggies; till at last an enterprising Yankee even opened a refreshment room.