nd of
the American Association for the Advancement of Science, who declined
the actual trial as too severe a task, estimated his probable time
with ordinary figures at twenty minutes, with strong chances of a
wrong result, after all.

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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