120 



KNOWLEDGE 



[Flu. -JS, 1883. 



the otiier two monkeys which tlio artist has tried, though 

 vainly, to picture with an expression as evil as tliat familiar 

 to those who have ever had occasion to pass through St. 

 Giles's or the Bowery, or certain ([uarters of Paris, Vienna, 

 San Francisco, Melbourne, Sydney, and other large cities. 

 If our first parents had heen repre.sented by two handsful 

 of dust on the one hand, and by Infinite Space and Infinite 

 Time on the other, the comparison would have been nearer 

 the truth. 



But when we turn from the follies which have Leen 

 uttered about that particular part of the doctrine of evo- 

 lution which we owe to Darwin, to consider the grave and 

 well-weighed utterances of the student of biology, the vanity 

 of the dust and uproar raised by the opponents of the 

 general doctrine over this particular point is clearly recog- 

 nised. The specific objections of an Owen, or an Agassiz, 

 or a Mivart, which leave the general doctrine untouched, 

 do not concern us in this respect. They relate to the way 

 in which evolution took place, not to the fact of evolution ; 

 they concern the extent to which the struggle for life has 

 affected development, not its existence as a factor in biolo- 

 <.ioal evolution. 



Consider the following propositions, on which Darwin's 

 theory rests, which we abridge from Dr. Wilson's treatise, 

 and note how little open to doubt is each one of them : — 



1. No two individuals of any species of plauts or of 

 animals is alike, none conform exact!// to a normal form of 

 the species. 



2. These variations, by natural laws of inheritance, 

 may be, and are, transmitted to the ofispring. 



3. More animals and plants are produced than can pos- 

 sibly survive. Each, if its natural increase were unchecked, 

 would alone suffice to fill the whole earth in a few thousand 

 years at the outside. 



4. The conditions under which animals live are con- 

 tinually undergoing physical change. 



5. Since all cannot live, there must be an endless 

 struggle for life, in which, on the average, the fittest will 

 prosper best; and, as the physical conditions are ever 

 changing, 



6. The variations named in 1 come into play, those 

 which tend to increase the fitness of a species being encou- 

 raged, so that 



7. New varieties are produced, which in time form new 

 races, and these in time new species. 



8. Past time (in the earth's history) has been, to all 

 intents and purposes, infinite — so that prohahly all the 

 existent species have had their origin in evolution from a 

 few simple forms. 



Yet hundreds of thousands of years ago the variety of 

 life on this earth may not have been very much less than 

 now. We may even look back to an exceedingly remote 

 time when the earth's condition was changing much more 

 rapidly than it does now, for the time when the chief work 

 of the difi'erentiation of species was brought about ; nor is 

 it wholly improbable that at a remote epoch in the earth's 

 past history those sudden variations which now occur but 

 seldom (as in the case of the Ancon sheep, itc. ), may have 

 been frequent, ai\d so new varieties, races, and species 

 may have been formed in shorter periods of time than now. 



Sexual selection would also have its influence in modi- 

 fying races, and forms an important part of the modern 

 theory of biological evolution. 



Dr. Wilson goes carefully and in a most instructive 

 manner through the general evidence on which the modern 

 theory of biological evolution is based. We can imagine 

 few who can either fail to understand his clear account, or 

 fail to be satisfied by the overwhelming weight of evidence. 



One feels that an eflbrt such as is made liy certain well- 

 meaning persons to reject the evidence of nature in this 

 respect is not merely ollering to God the unclean sacrifice 

 of untruth, but involves the belief that His works are 

 themselves untruthful, since these works teach the lesson of 

 evolution so distinctly. 



In the earlier chapters Dr. Wilson explains the methods 

 in which biological studios are pursued, the constitution of 

 the animal and plant worlds, and the relations of proto- 

 plasm to life. He then discusses the evidence derived from 

 rudimentary organs, from the gradual modifications of 

 animal structure, from likenesses, and from "found links" 

 (which involves the explanation of " missing links "). The 

 ninth, tenth, and eleventh chapters deal with the evidence 

 from development, giving much space (though he might 

 have given more, could he have afTorded it) to the deduc- 

 tions from the embryology of vertebrates. He shows but 

 briefly — yet the evidence is conclusive enough — that, v.-hat- 

 ever the meanimj (if the fact mail he, man's development is 

 but an epitome of that of lower forms of life. The twelfth 

 chapter, dealing with that strangely fascinating suV>ject, the 

 metamorphosis of insects, is full of interest. The other 

 chapters discuss the evidence from the constitution of 

 compound animals, the fertilisation of flowers, the evidence 

 from degeneration (an essential part of the theory of de- 

 velopment) : and lastly, the relations of geology to biological 

 evolution. 



The work is sound and thorough, as well as interesting. 

 Though not a small book, it may be regarded as an abridg- 

 ment of the multitudinous evidence on which the modern 

 theory of the evolution of various races and species 

 depends. 



The electric light has been adopted by !M. Lazare Weiller, 

 manufacturer of phosphor and silicious bronze telephone and 

 telegraph wires, at his extensive works at Angouleme. It 

 is stated that the price of gas there is about 8s. 4d. per 

 l,0(iO ft., and to produce a total luminosity of .515 carcels 

 (nearly -5,000 candles) would cost 26677 francs (2.5-63 

 pence) hourly. Instead of gas, five Gramme arc lamps 

 and fifteen Swan incandescent lamps are used, at an 

 estimated total cost of 1'21 francs (11 61 pence) per 

 hour. A saving of 1-46 francs per hour is thus effected. 

 The total cost of the installation was 6,215 francs (£248 6), 

 not reckoning about 1,000 francs for fixing, belting, itc. 

 This would be more than made good in three years' 

 working at 2,400 hours per annum. M. Weiller, there- 

 fore, consulted his best interests in thus adopting a light 

 which, while it performs its functions much better than 

 gas, is considerably cheaper. 



The Westminster Aquarium Electric Light Exhibition 

 promises to be the most complete yet held. It has been 

 very slow in starting, the opening having been several 

 times postponed. We wish it every success. 



Some remarkal>le archa'ological discoveries have recently 

 been made at Mitla, a village in Mexico, situate 

 between twenty and thirty miles from Oajaca, in the 

 table-land of Mixtecapan. Extensive remains of ancient 

 palaces and tombs have been revealed, and it is stated 

 that they are exceptionally remarkable from the columns 

 supporting the roof, a style of architecture peculiar 

 to the district of Mexico in which they have been found. 

 These ruins have been explored and photographed by Herr 

 Hcmil Herbruger, who states that the great hall contains 

 six columns, and is 37 metres long by 7 broad. Each 

 column is 37i metres in height, and is of solid stone. — 

 Engineer. 



