There is value in the teaching which teaches the eye what to observe; at times there is gain in a freshness of view unwarped by ideas as to what deserves to be inspected and what does not. Dr. Priestley, one of the founders of chemistry, says:--“I do not at all think it degrading to the business of experimental philosophy to compare it, as I often do, to the diversion of hunting, where it sometimes happens that those who beat the ground the most, and are consequently best acquainted with it, weary themselves without starting any game, when it may fall in the way of a mere passenger; so that there is but little room for boasting in the most successful termination of the chase.” True, yet this discerning eye will always be found beside a brain of uncommon force and sweep. Mr. Edwin Reynolds, of Milwaukee, as related in this book, never saw a mining stamp until the morning when he planned a bold and profitable simplification of it. Professor Alexander Graham Bell, who invented the telephone, came to his triumph not as a disciplined electrician, but as a student, under his father, of articulate speech and its transmission. He has told me that had he known the obstacles to be surmounted, he would never have begun his attack. Professor Ernst Abbe, of Jena, who more than any other investigator is to be credited with the production of Jena glass, was at the outset of his labors quite ignorant of practical optics. But he had a thorough mastery of mathematical optics, and this in due season enabled him to revise the theory of the microscope, and to prescribe the conditions according to which the manufacture of totally new kinds of glass should proceed. Every one of these men, every peer they have ever had among the volunteer forces of research, is far removed in native ability, in plasticity of mind, from Priestley’s “mere passenger.” If ignorance by itself were the chief qualification for discovery, science would long ago have entered upon its golden age. Any Observation May Have Value. Michael Faraday, that consummate observer, held that at times the observations of comparatively untrained men are well worth attention. In one of his note-books he wrote:--“Whilst passing through manufactories and engaged in the observance of the various operations of civilized life, we are constantly hearing observations made by those who find employment in these places, and are accustomed to a minute observation of what passes before them which are new or frequently discordant with received opinions. These are frequently the result of facts, and though some are founded in error, some on prejudice, yet many are true and of high importance to the practical man. Such of them as come in my way I shall set down here, without waiting for the principle on which they depend; and though three fourths of them ultimately prove to be erroneous, yet if but one new fact is gathered in a multitude, it will be sufficient to justify this mode of occupying time.”