MECHANICS AND USEFUL ARTS. 35 



to us more especially their chemical ones ; and it is only by combining the 

 information obtained from these two sources, together with those from hot 

 springs, especially as regards the gaseous products of each, that we can ever 

 hope to penetrate the veil which shrouds the operations of this mysterious 

 agent ; so as to pronounce with any confidence, whether the effects we witness 

 are due, simply to that incandescent state in which our planet was first 

 launched into space, or to the exertion of those elective attractions which 

 operate between its component elements, attractions which might be sup- 

 posed to have given rise, in the first instance, to a more energetic action, and 

 consequently to a greater evolution of heat, than is taking place at present, 

 when their mutual affinities are in a great measure assuaged. "Within the last 

 twenty years much has been done towards the elucidation of this problem 

 through the united investigations of Boussingault, of Devflle, and above all 

 of Bunsen, with respect to the gases and other bodies evolved from volcanoes 

 in theh- various phases of activity ; the results of which, however, do not 

 appear to me to present anything irreconcilable with that view of their 

 causes which was put forth many years ago in the work I published. 

 Whilst, however, the latter is offered as nothing more than as a conjectural 

 explanation of the phenomena in question, I may remind those who prefer 

 the contrary hypothesis, on the ground that the oblate figure of the earth is 

 in itself a sufficient proof of its primaeval fluidity, that this condition of things 

 could only have been brought about in such materials by heat of an intensity 

 sufficient, whilst it lasted, to annul ah 1 those combinations amongst the elements 

 which chemical affinity would have a tendency to induce, and thus to render 

 those actions to which I have ascribed the phenomena not only conceivable, 

 but even necessary consequences, of the cooling down of our plaaet from its 

 original melted condition. 



Such are a few of the additions to our knowledge which have been made 

 in the course of the last twenty years in those sciences with which I am most 

 familiar. Whilst, however, the actual progress which has taken place in them 

 is in itself so satisfactory, the change which the sentiments of the public have 

 undergone with respect to their claims to respect, affords no less room for 

 congratulation. 



The extension, indeed, which is now given to the name of Museum in the 

 language of naturalists, and even by the public at large, is hi itself an indica- 

 tion of correcter views than were formerly entertained, with regard to the 

 uses of such establishments. Few, for instance, have such a notion of a 

 Museum as Horace Walpole gave utterance to at the close of the last cen- 

 tury, when he defined it " a hospital for everything that is singular whether 

 the thing has acquired singularity from having escaped the rage of time, from 

 any natural oddness, or from being so insignificant that nobody thought it 

 worth w T hile to produce any more of the same." " The stuffed ducks, the 

 skeleton in the mahogany case, the starved cat and rat which were found 

 behind the wainscot, the broken potsherd from an old barrow, the tattooed 

 head of the New Zealand chief, the very unpleasant-looking lizards and 

 snakes coiled up in the spirits of wine, the flint stones and cockle-shells, &c., 

 will no longer be seen jumbled together in heterogeneous confusion," as 



