266 Pleasant Ways in Science. 



of water, spread out over a considerable surface, to keep it 

 alive two or three years. But by adopting this liberal rule, 

 we make an end of the necessity for asrating, and for fre- 

 quently renewing the stock of plants and animals. 



PLEASANT WAYS IN SCIENCE. 



NO. I. — CUEIOSITIES OF MOTION. 



Under this title we propose from time to time to consider 

 divers scientific questions in an informal manner, seizing rather 

 upon their amusing, pictorial, or ideal aspects than attempting 

 to build them up into the technical form of a methodical trea- 

 tise. Our object is to bring interesting results within the 

 reach of those who may not have time or opportunity for 

 arriving at them through a regular course of study, and to 

 render assistance to those who diligently collect facts, but 

 require help in. the art of associating them together, so as to 

 form a philosophy. We shall begin with some entertaining 

 facts concerning Motion. 



Of all earth's millions of human inhabitants how few know 

 when they awake in the morning what enormous journeys 

 they must take before the day will be over, and the dawn of 

 the morrow will greet their eyes. It would alarm a Londoner 

 to tell him at daybreak that he should be shot off to Persia 

 with the speed of a rifle bullet ; and indeed we know no arti- 

 ficial mode of spinning him onward at anything like such a rate, 

 even for short distances, with due regard to the continuance of 

 his life. Nature, however, rolls him along with tremendous 

 speed as the earth careers from west to east. In the course of 

 twenty-three hours fifty-six minutes, four seconds, and nine 

 hundredths of a second, the earth turns round on its imaginary 

 axis. If at any moment we thought ourselves upright, we 

 must remember that since that moment flitted away, we have 

 been turned topsy-turvy, and brought right again exactly in 

 that space of time. How do we know this ? It is one of the 

 many things which the stars tell those who worship them 

 with the homage which science pays to their brilliant and yet 

 -unseen orbs.* If we set up a tall convenient mark, or take a 

 distant church spire, a lightning rod or a flag-staff, and note 

 when any particular star is exactly over it, in precisely the 

 time we have given, that star will be again in its place ; and as 



* The reader may consider as part of this series the paper, " We never See 

 the Stars," which 6ee to explain the paradox in the text. (See Vol. v., p. 47.) 



