HYPOTHESIS

"The earth hath bubbles, as the water has, and these are of them."    —Shakspere.

"Substantial progress in any science is impossible in the absence of a working hypothesis, which is universal in its application to the phenomena pertaining to the subject matter."

Paint-making has been rescued from the domain of empiricism and has become an exact science. One skilled in it can now practise it with a certainty of results, in an exact proportion to his knowledge of its principles, and to his ability in applying them to work in hand.

The theory that oil, or the binder, is the

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