646 ANNUAL, BEPGRT 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 



