io THE WORLD MACHINE 



detailed conception of the cosmic Reality. In any event, 

 whether this prove true or no, this surely is certain, that our 

 present-day ideas of creation represent the highest flight, or 

 in varied metaphor, the loftiest monument of the human mind 

 which we possess. 



I wish to trace out the path and the method by which these 

 ideas, these results, have been reached. Hereafter I shall 

 present an argument, describe a doctrine, point out, as it were, 

 the moral of the tale. But first of all there is need of a con- 

 nected presentation of the facts. From age to age there have 

 been various attempts towards such a complete world-picture. 

 Their value naturally becomes impaired with the advance of 

 knowledge. Such an idea was more or less the basis of the 

 Hebraic Pentateuch, and indeed the fundament of almost all 

 religious systems has been an attempt towards an intelligible 

 cosmogony. Such a work too, we may conjecture, was the 

 Diakosmos of Democritus, written in the fourth century B.C., 

 but now lost to us. A similar attempt is seen in Pliny's 

 Natural History, in the first century A.D. ; in the works of 

 Roger Bacon, the Admirable Doctor, in the thirteenth century ; 

 in the Imago Mundi of Cardinal d'Ailly, which was the inspira- 

 tion of Columbus ; in the Natural History of Buffon and in 

 many another. 



In our own day the most noteworthy endeavour towards a 

 complete physical description of cosmos was that made more 

 than half a century ago by Humboldt. It was begun long after 

 that splendid mind had passed the customary limits of pro- 

 ductivity, before the doctrine of the conservation of energy had 

 been established, and before it came to be understood that the 

 sun is a cooling body whose light and life may one day die 

 out with it the light and life of the tiny bits of worlds which 

 flutter in circles about him. In no later single work has 

 Humboldt's vast design been realised. Such a work would be 

 a summation, and more, of the physical sciences in their present 

 state ; the task is probably beyond the powers of any single pen. 



The same is true of the historical side. The full story of 

 the slow growth of this body of knowledge, of theory, and of 

 ideas, is to be found only in pages the most diverse. It has 

 been dealt with in a variety of works, rather drearily by Whewell, 

 rather dreamily by Apelt, with a good deal of bias by Draper, 



