These statistics prove the existence of a class of persons who can do faster and more reliable work by the binary reckoning.  But too much should not be made of them.  Let them serve as specimens of facts of which a great many more are to be desired, bearing on a question of grave importance.  Is it not worth our while to know, if we can, by impartial tests, whether the tax imposed on our working brains by the system of arithmetic in daily use is the necessary price of a blessing enjoyed, or an oppression?  If the strain produced by greater complexity and intensity of mental labor is compensated by a correspondingly greater rapidity in dealing with figures, the former may be the case.  If, on the contrary, a little practice suffices to turn the balance of rapidity, for all but a small body of highly drilled experts, in favor of an easier system, the latter must be.  This is the question that the readers of Science are invited to help in deciding.  The difficulties attending a complete revolution in the prevalent system of reckoning are confessedly stupendous; but they do not render undesirable the knowledge that experiment alone can give, whether or not the cost of that system is unreasonably high; nor should they prevent those who accord them the fullest recognition from assisting to furnish the necessary facts.

Those who are willing to undertake the addition on the plan proposed or on any better plan, or who will submit it to such acquaintances, skilled or unskilled, as may be persuaded to take the trouble to learn the mechanism of binary adding, will confer a great favor by informing the writer of the time occupied, and number of mistakes made, in each addition.  All observations and suggestions relating to the subject will be most gratefully received.

Henry Farquhar.

Office of U.S.  Coast Survey, Washington, D.C.

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