152 On Bryin-Work and Hand-Work . [March, 
more distant than the point of gravitation ; the solar dis- 
tance of Mercury becomes — 
176 r 
172 x 1*22 
= 82*8 r. 
A tertiary perturbation here becomes perceptible. 
(To be continued.) 
V. ON BRAIN-WORK AND HAND-WORK. 
By R. M. N. 
T may seem presumptuous in me to take up a subject 
which has been ably dealt with some years back in the 
“Journal of Science,” by occasion of Dr. Beard’s 
treatise on the “ Longevity of Brain-Workers.” Still it 
appears to me that the last word on this topic has not yet 
been said. Certain points, both of distinction and of resem- 
blance, seem to have been overlooked as well by reviewer as 
by author, and certain of the conclusions drawn are at least 
open to question. 
I may perhaps be allowed to put the opening question, 
What is work? The common reply is, “Any pursuit by 
which a man earns or attempts to earn a livelihood, and to 
accumulate wealth.” This definition is the more to be re- 
gretted because it cherishes, or rather begets, the vulgar 
error that all persons who do not aim at the accumulation 
of wealth are “ idlers.” In point of faCt such men may be 
doing far greater services to the world than the most diligent 
and successful votary of a trade or a profession. Darwin, 
having a competency, was therewith content. To him, and 
to others of kindred minds, the opportunity of devoting his 
whole life to the search after scientific truth was a boon 
immeasurably higher than any conceivable amount of 
wealth. Shall we call him an idler ? Nor is Science the 
only field which opens splendid prospers to men of inde- 
pendent means. Art, literature, philanthropy, have all their 
departments, unremunerative in a commercial point of view, 
