The Reverend Albert H. Plumb, of Roxbury, Mass., who has followed Mr. Keely's efforts, to obtain control of the unknown force which he discovered more than twenty years ago, up to his present successful demonstration before scientists, says: "Neither theological science nor any department of physical science, as it lies in the divine mind, is exactly expressed in any human system; yet no knowledge is to be decried nor despised, least of all in the highest realms of thought. The agnostic makes the mistake of confounding exhaustive knowledge with positive knowledge in declaring both unattainable. We can know positively that a thing is, if not how or why it is. As Gladstone says, 'Our hands can lay hold of truths which our arms cannot embrace. We can apprehend what we cannot comprehend.' If Keely should die, I fear no one could understand his writings. Every day we read of distinguished men dying. The other day a man carried with him into the grave his secret for the cheap production of aluminium. No one man entrusted by Providence with high interests has a right to allow a possibility of their sinking back, perhaps for ages, into the void of the unknown. Why not confine attention strictly to making the discovery practically intelligible to others, and thus securing to mankind the first steps by which the new force is evoked and controlled, and leave to later leisure the subtler relations of this power to the divine mind and to life?" For years Mr. Keely did "confine attention" to efforts to prove his discovery by practical methods, without making any advance; and it was not until he was led into the spiritual or philosophical bearings of his discovery that he himself gained "practically intelligible" ideas of its nature. To Dr. Macvicar's "Sketch of a Philosophy," from which Mrs. Moore compiled "Ether the True Protoplasm," and to Mrs. Hughes' book on the evolution of tones and colours, Mr. Keely is indebted for the pregnant germs which, falling from their writings upon his mind, took him from the line of experiment which he was pursuing, into the only line of research which can lead to scientific and commercial success. The hour in which he reaches one he reaches both; nor can one be gained without the other being gained. This should teach us that, though "the heart of man deviseth his way, the Lord directeth his steps." God never hurries, and He chooses His own instruments, employing them after a manner that is inscrutable to us, in our weak impatience for results. Admitting the truth of all that Dr. Plumb has said, but understanding fully the impossibility of directing Mr. Keely's steps, until he himself gains more control of the force that he has discovered, we must "wait upon the Lord," who is revealing to him "the deep mysteries of Creation." In the meantime, those in whom narrowness of mind has not caused stubbornness will hold themselves in readiness to prove all things and hold fast to the truth. We do