August 31, 1&?3.] 



SCIENCE. 



279 



will venture to do so. If, therefore, life exists in 

 other parts of this groat universe, does it necessarily 

 occupy bodies of protoplasm in those ditTerent, remote 

 spheres ? It would he a great assumption. It is al- 

 together improbahle. The certainty is, that in those 

 planets which are in pro-ximity to the sun's heat 

 there could be no protoplasm. Protoplasm in the 

 remote planets would be a hard mineral, and ue.ar 

 the sun it would be dl>sipated into its component 

 gases. So that, if life be found in other parts of this 

 universe, it must reside in some different kind of 

 material. It is extremely probable that the physical 

 conditions that reside in protoplasm might be found 

 in other kinds of matter. It is in its chemical inert- 

 ness, and in its physical constitution, that its adap- 

 tation to life resides; and the physical constitution 

 necessary for the sustentation of life may be well 

 supposed to exist in matter in other parts of the uni- 

 verse. I oidy say the door is open, and not closed: 

 any one who asserts that life cannot exi^t in any 

 other material basis than protoplasm is assuming 

 more than the world of science will permit him to 

 assume. And that it is confined to this single planet, 

 and not in the great systems of the universe, — that 

 assumption will not for a moment be allowed. There- 

 fore the subject is one which allows us a free field 

 for future investigation: it is by no means closed in 

 the most important laws which it presents to the 

 rational thinker. I hope, therefore, that, if the evi- 

 dence in favor of this hypothesis of the creation of 

 living forms be regarded as true, that no one will 

 find in it any ground for any very serious modifi- 

 cation of existing ideas on the great questions of right 

 and wrong which have long since been known by 

 men as a result of ordinary experience, and without 

 any scientific demonstration whatsoever. 



A classification of the natural sciences.^ 



BV T. STEKItV HUNT, I.L.D., F.K.S., OF MOXT.'tE.VL. 



To frame a ration.al classification of the natural 

 sciences, and to define their mutual relations, have 

 often been attempted. The present writer, in an 

 essay read before tfta National academy of sciences 

 in April, 1881, and since published in the Philosophi- 

 cal magazine, with the title of 'Thedom.iin of phy- 

 siology,' suggested the basis of such a scheme, and 

 now. at the re(|uest of some of his readers, ventures, 

 for the first time, to embody in a concise and tabu- 

 lated form the views then and there enunciated, in 

 the hope that other students may find it not imworthy 

 of their notice. 



The study of material nature constitutes what the 

 older scholars correctly and comprehensively termed 

 physics (the words 'physical' and 'natural' being 

 synonymous), and presents itself in a twofidd aspect, 



— first, as descriptive; and, second, as philosophical, 



— a distinction embodied in the terms 'natural his- 

 tory' and 'natural philosophy,' or, more concisely, 

 in the w<jrds ' physiography ' and ' physiology.' The 

 Latter word has been employed, in this general sense, 

 to designate the philosophical study of nature from 



I Abntract of paper read In general acssion, Aug. 17, 1883. 



the time of Aristotle, and will so be used in the pres- 

 ent classification. 



The world of nature is divided into the inorganic 

 or mineralogical, and the organic or biological, king- 

 doms; the division of the latter into vegetalde and 

 aidmal being a subonlinate one. The natural history, 

 or physiography, of the inorganic kingdom, takes cog- 

 nizance of the sensible characters of chemical species, 

 and gives us descriptive amt systematic mineralogy, 

 which have hitherto been restricted to native species, 

 but, in their wider sense, include all artificial species 

 as well. The study of native mineral species, their 

 aggregations, and their arrangement as constituents 

 of our planet, is the object of geognosy and physical 

 geography. The physiography of other worlds gives 

 rise to descriptive astronomy. 



The natural philosophy of the inorganic kingdom, 

 or mineral physiology, is concerned, in the first place, 

 with wh.at is generally called dynamics or phy>ics; 

 including the phenomena of ordinary motion, sound, 

 temperature, radiant energy, electricity, and magnet- 

 ism. Dynamics, in the abstract, regards matter in 

 general, without relation to species; chemism gener- 

 ates therefrom mhieralogical or so-called chemical 

 species, which, theoretically, may be supposed to be 

 formed from a single elemental substance, or tiinteria 

 prima, by the chemical process. Dynamics and chem- 

 istry build up our inorganic world, giving rise to 

 geogeny, and, as applied to other worlds, to theoreti- 

 cal astronomy. 



Proceeding next to the organic kingdom, its physi- 

 ographical study leads us first to organography, and 

 then to descriptive and systematic botany and zoology, 

 two great subilivisions of natural history. Coming, 

 then, to consider the physiological aspect of organic 

 nature, we find, besides the dynamical and chemical 

 activities manifested in the mineral, other ami higher 

 ones which characterize the organic kingdom. On 

 this higher plane of existence, are fnuiid portions of 

 matter which have become individualized, exhibit 

 irritability, the power of growth by assimilation, and 

 of rcproductiim, and which establish relations with 

 the external world by the development of on;ans, all 

 of which char.icters are foreign to the mineral king- 

 dom. These new activities are often designated as 

 vital; but since this word is generally made to in- 

 clude at the same time other manifestations which 

 are simply dynamical or chemical, I have elsewhere 

 I)roposed for the activities characteristic of the organ- 

 ism the term biotics (/3ioT«6f, pertaining to life). The 

 idiysiology of matter in the abstract is dynamical, 

 that of mineral species is both dynamical and chemi- 

 cal, while that of organized forms is at once dynami- 

 cal, chemical, and biotical. All of these, I may 

 remark, I regard as successive manifestations of an 

 energy inherent in matter. ■ 



The study of the bintical activities of matter leads 

 to organogeny and morphology, while the relations 

 of organi.-ms to one another and to the inorganic 

 kingdom give ns physiological botany and zoology. 

 We thus arrive at a comprehensive and simple 

 scheme of the natural sciences, which I have endeav- 

 ored to set forth in the subjoined table. 



