646 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1911. 
which would be even quite good along the open road to Brighton, 
would be considered decidedly on the high side for motoring along 
the Strand. Our ideas of what is slow and what is fast are largely 
derived from habit, and particularly from surrounding conditions and 
from our mode of estimation. For instance, we have been carried in 
this hall during the last hour with the surface of the earth round its 
axis a distance of about 600 miles. ‘This speed would require a line 
on our speed chart about as high as the dome of the hall to represent 
it graphically. But if we judge the speed from observing the 
apparent rate of motion of the moon and stars overhead, we could 
never realize this. Far less could we realize by the change in the 
seasons the speed at which we are traveling with the earth round the 
sun, accomplishing a distance, as we do, of 540 million miles in 365 
days, which represents roughly, a distance of 60,000 miles per hour. 
We have thus traveled together, since we came into this hall, a speed 
of 60,000 miles. The line required on our chart for this speed would 
be about as high as St. Paul’s Cathedral. But these speeds fall far 
short of those of certain heavenly bodies with which we are familiar, 
such as the meteors, some of which are traveling at 160,000 miles an 
hour, and the recent comet, which probably exceeded this speed one 
part of its journey round the sun; whereas the fastest speed which 
man has, up to the present, been able to produce, even in a projectile, 
amounts to between 2,000 and 3,000 miles an hour (the Krupp 10.7 
centimeter having a velocity of 3,291 meters per second, and a 6-inch 
Vickers, 3,190 meters per second). The highest projectile speeds we 
have attained are thus only about one-tenth of the speed at which 
Jules Verne fired M. Barbicane and his friends off, in order to over- 
come the earth’s gravity and reach the moon, since the speed he 
required was 12,000 yards per second, or 24,000 miles per hour. 
Such an idea we are quite justified in thinking absurd, but we might 
have been justified in thinking many of the things absurd which Jules 
Verne wrote about, only 40 years ago, and which have since come 
to pass. Take Round the World in Eighty Days. In that case it 
cost Phineas Fogg £19,000 to take himself and his servant round the 
world in 80 days. A telephone inquiry of Messrs. Cook an hour or 
two ago elicited the fact that anyone present can start to-morrow 
morning and go round the world, with a servant, in less than half the 
above time, and for less than one-fiftieth of the above sum. 
Thus though, impelled by instinct, man will ever continue to strive 
to increase his speeds of traveling, and with the refinement of machin- 
ery and invention doubtless succeed in doing so, it may be safely 
said that, notwithstanding the still increasing upward angle on some 
of the speed lines of the charts I have shown to-night, this rate of 
increase will before long begin to take place at a continually diminish- 
ing rate. Such feats as the journey from Paris to London within the 
