112 



KNOWLEDGE 



[May 1, 1897. 



Titanotherium, been discovered there, but the remains of 

 dinosaurian reptiles are met with in a state of perfection 

 to -which there is no comparison in other parts of the 

 globe. These complete skeletons have not only fully 

 borne out the speculations of Huxley and Hulke as to the 

 close structural resemblance between these reptiles and 

 birds, but have also shown how nearly the restorations 

 attempted by the English anatomists approached the 

 reality. Equally important have been the palseontological 

 discoveries in South America : discoveries which indicate, 

 without doubt, a former Tertiary land connection between 

 that continent and distant Australia. To even allude to 

 some of the palreontological discoveries among the lower 

 groups of animals is obviously impossible in the space 

 at our disposal. 



Since the publication of the " Origin of Species " 

 several new doctrines in connection with the evolution of 

 animal life have been propoimded. Among these, one of 

 the most important, and one which has probably played a 

 very considerable part in nature, is that of parallelism in 

 development : that is to say, the independent develop- 

 ment of similar structures in different groups of animals 

 living imder similar circumstances, or in course of adapta- 

 tion to similar conditions of life. Mimicry, too, is another 

 important factor in nature, the discovery and recognition 

 of which has taken place during the Queen's reign. The 

 cutting of thin sections of animal and vegetable tissues, 

 and their examination under the microscope, and the 

 wonderful results that have been obtained thereby, are 

 also a development of the reign, as is likewise microscopy 

 in general. Bacteria and microbes, again, are low types 

 of life whose investigation forms one of the greatest 

 achievements of the latter part of the era, and the 

 incalculable benefits which have already been conferred 

 on suffering humanity by this line of study, are well 

 known to our readers. 



Systematic zoology and botany have passed through 

 several stages during the period imder review. As already 

 said, at the commencement of the reign the former was 

 labouring under the thrall of the circular hallucination, 

 from which, however, it at length cast itself free. Since 

 that time a steady progress has, on the whole, been made 

 in most branches, as anyone may satisfy himself who 

 contrasts the Linnean system (which was chiefly in vogue 

 in 1836) with that to be foimd in any of the better class of 

 modern text-books. And here it may be mentioned how 

 vastly superior are these to their predecessors of half a 

 century ago. Whether the progress has been equally 

 satisfactory on the species question may well be doubted. 

 Even early in the reign gibes and taunts were freely 

 levelled at the " species monger," and it was thought by 

 many that the pubUcation of the " Origin of Species " 

 would be the death-kuell of the abstraction fi-om which it 

 took its name. For a time, indeed, there was a lull, 

 and naturalists seemed inclined to take a broader and 

 more philosophic estimate of the amount of differences 

 which ought to be regarded as of specific importance. 

 But of late years, and especially in America, species- 

 making has once more taken a new lease of life, and 

 every little more or less constant difference is now 

 regarded as of specific or " sub-specific " value. Indeed, 

 we have even heard it whispered that a " species " of 

 snail has been restricted to the individuals inhabiting a 

 particular tree-trunk. As in stamps, refinement in making 

 distinctions is almost an inseparable sequence of ai-dent 

 collecting ; but it is permissible to doubt whether the hair- 

 splitting in this respect, characteristic of the present 

 decade, will eventually be included in the biological 

 progress of the Victorian era. 



SIXTY YEARS OF GEOLOGICAL RESEARCH. 



By Grenville A. J. Cole, M.E.I. A., P.G.S., 



Professor of Geology in the Royal ('allege of Science for 

 Ireland. 



AS is the case with all other sciences, the progress 

 of geology has become more rapid, and its results 

 have become more appreciated, in proportion to 

 the spread of education among the peoples as a 

 whole. Even in the old days of book-learning, 

 pupils were at least trained to read books, and hence the 

 discoveries of scientific men became in due time accessible 

 to the many. Gradually it was seen that in the observa- 

 tion of the world around us lay the only safe clue to the 

 history of that world in long-past ages ; and a band of 

 workers arose about the beginning of this century, 

 prepared to treat geology as a branch of natural history, 

 rather than as a ground for dogmatic contention and for 

 the exploitation of theories of cosmogony. 



Already, in 1807, the foundation of the Geological 

 Society of London had brought together serious observers, 

 and had provided a meeting-ground for those interested 

 in the mineral or the pahrontological aspects of the 

 earth. The Geological Society of Dublin commenced 

 its publications in 1832, that of Liverpool in 1859, and 

 that of Glasgow in 1861 ; while the well-known Geologists' 

 Association, founded in 18.58, has kept hundreds in constant 

 touch with the field-work which is the foundation of 

 geological discovery. Thanks to the steady growth of 

 this organization, and of the " field clubs," whose best 

 meetings are held in the open air, geology has assumed 

 its place at the present time as one of the most attractive 

 sciences ; and its human aspect, the insight that it gives 

 us into the long chains of life-forms which preceded the 

 appearance of man upon the globe, affords it, in our 

 evolutionary days, increased importance and vitality. 



The general spread of some knowledge of chemistry 

 and physics in our schools and institutes — I write, at 

 least, of England and of Scotland — promises that the new 

 observers in geology will receive a more rigid training than 

 was customary sixty years ago. In 1830 Lyell published 

 the first volume of his famous "Principles of Geology"; and 

 he still found arrayed against him those who preferred 

 rapid speculation to steady observation, and the reporting 

 of "curiosities of travel" rather than the recording of 

 connected details. Though Lyell himself cannot (mainly 

 on account of his defective eyesight) be classed among the 

 great geological discoverers, yet his methods of work, his 

 continual adaptation of the known processes of the present 

 to the explanation of past phenomena, make him rank 

 among the foremost teachers of the age. His caution, his 

 very respect for the recurring cycles of James Hutton 

 (1795), who had founded the " uniformitarian " school, 

 made him at first sceptical as to the reality of organic 

 evolution ; but his acceptance of the views of Darwin and 

 Wallace, very shortly after the publication of the " Origin 

 of Species," gave a great and further stimulus to geology. 

 Geology has since gone hand in hand with zoology in 

 seeking to unravel the past history of the earth ; and the 

 catastrophic school, of which even Cuvier was a supporter, 

 has reserved its epochs of deluge and explosion for periods 

 before life existed on the globe. 



With the acceptance of rational views as to the origin of 

 the rocks which we see around us, the systematic study of 

 the organic remains found in them became a matter of 

 more serious interest. The foundations of historical 

 geology had been laid by William Smith, the laud surveyor 

 and engineer, between 1790 and 1815 ; and Lyell's classifi- 

 cation of the stratified rocks that were formed nearest to 



