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 tained the law of descent. This was an important achievement, because, having become familiar with the precise rate of descent at all depths, they were enabled to tell very nearly when the ball ceased to carry out the line, and when it began to go out in obedience to the influence of currents. The greatest depth reached by Brooke’s is said to have been a little under five miles—in the North Atlantic.

The value of investigations of this kind does not appear at first sight, to unscientific men. But those who have paid even a little attention to the methods and processes by which grand discoveries have been made, and useful inventions have been perfected, can scarcely have failed to come to the conclusion that the search after, pure and simple, of any kind, and of every kind, either with or without reference to a particular end, is one of the most useful as well as elevating pursuits in which man can engage.

All truth is worth knowing and labouring after. No one can tell to what useful results the discovery of even the smallest portion of truth may lead. Some of the most serviceable and remarkable inventions of modern times have been the result of discoveries of truths which at first seemed to have no bearing whatever on those inventions. When James Watt sat with busy reflective mind staring at a boiling kettle, and discovered the expansive power of steam, no one could have for a moment