592 



NATURE 



\pct. 3, 1878 



of very common but most ancient potsherds indicate 

 the existence of an ancient rustic habitation, which 

 Homer appears to have described to us as the house and 

 station of Eumaeus. This is the more probable as at a 

 very short distance to east of this site, and near the sea, 

 is a white cliff with a perpendicular descent of 100 feet 

 which imtil now is called Korax — i.e., the Raven Rock, 

 to which Homer refers when he represents Ulysses as 

 challenging Eumaeus " to precipitate him from the great 

 rock " if he finds that he is telling lies (Od. xiv. 398). 

 Below the Korax, in a recess, is natural and always 

 plentiful pure water, which the tradition identifies with 

 Homer's fountain of Arethusa, from which Eumseus's 

 swine were watered. Dr. Schliemann excavated as well 

 in the stables as in front of them on the site of the rustic 

 habitation ; the stable he found filled with stones, but on 

 the site ?of the house he struck the rock in a depth of 

 one foot, and found there fragments of very interesting, 

 most ancient, unpainted pottery, also of pottery with red 

 bands, and masses of broken tiles. 



Dr. Schliemann states that Ithaca is, like Utica, a 

 Phoenician word, and means " colony," and that the type 

 of the Ithacans is decidedly Phoenician. According to 

 Homer Laertes's grandfather was Poseidon, and Mr. 

 Gladstone is therefore perfectly right that the descent 

 from Poseidon always means "descent from the Phoe- 

 nicians." 



Dr. Schliemann has obtained a new firman for Troy. 

 He left Athens on September 18 for the Troad to continue 

 his long interrupted excavation of Troy. His first work 

 will be to bring to light the whole of the mansion imme- 

 diately to the north and north-west of the gate, which 

 seems to belong to the ancient city's chief or king. 



ARE THE ''ELEMENTS'' ELEMENTARY ?^ 



'TPHE problem set before us by the words which I hare 

 ■•- chosen as a heading for this article is a vast one ; 

 unfortunately the data upon which an answer must be 

 founded are in themselves vague and meagre. It is use- 

 less attempting to draw an exact conclusion from inexact 

 data. If the degree of probability which attaches its'elf 

 to the data is small, the probability of the conclusion 

 being true must be yet smaller. 



In the times of the ancients men do not appear to have 

 attached any very definite idea to the word "Element." 

 An element was a something, a material or an imaginary 

 something — it did not very much matter which — a some- 

 thing which one might suppose, if one Avere so minded, to 

 form a sub-stratum upon which other, apparently more 

 complex, things rested. Fire was an element ; it was 

 supposed to enter into the constitution of matter of many 

 kinds. Some people said they believed that fire and 

 water formed earth of different kinds ; others averred 

 that air and Avater were the foundations of all things. 

 But it was perfectly legitimate for a third person to tell 

 the two former that they' were completely in error, that 

 really sulphur and salt were the primary elements, and 

 that from these all other forms of matter arose. 



No exact data concerning the possibility of transforming 

 earth into air, or water into fire, or salt into sulphur were 

 forthcoming. Men did not generally trouble themselves 

 with investigations into the actual properties of the so- 

 called elements. Everything was founded on supposition ; 

 the human mind was superior to nature, and could project 

 itself upon nature and explain nature. 



Such a method could lead to no true knowledge of 

 natural phenomena. To-day we have altered our method 

 of investigation. Nature presents us with a mass of 

 materials ; most of these we can decompose into two or 

 rnore forms of matter, but some of these resist all efforts 

 hitherto made to effect their analysis. The latter we call 



« A paper read before the Owens College Chemical Society. 



elements, the former compounds. Our knowledge is im- 

 perfect; we acknowledge the imperfection, but attempt 

 to make the knowledge exact so far as it goes. Whether 

 the so-called elements are or are not capable of further 

 subdivision is an open question. Whatever answer this 

 question may finally receive, the superstructure of chemical 

 science will remain unshaken. We may find it necessary 

 to alter the form of many statements ; the facts and, I 

 am persuaded, many of the theories, will remain. 



An element is then a substance which has hitherto yielded 

 no simpler form of matter than itself We make the hypo- 

 thesis that matter is built up or compounded of those 

 substances which we call elements. But this is of course 

 only an hypothesis. So long as we accept it as such it is 

 of the utmost service to us ; whenever we erect it into a 

 dogma it ceases to become an aid to the investigation of 

 nature, and begins to exercise a tyranny over us. 



An amusing and instructive instance of the narrowing 

 and deadening effect of accepting an hypothesis dogma- 

 tically is narrated in Prof Bryce's recently-published 

 book on Trans- Caucasia. Prof. Bryce accomplished the 

 ascent of Mount Ararat : tradition says that no one has 

 ever been to the summit of this mountain ; the inhabi- 

 tants of the neighbouring country have formed this 

 saying into a dogma which teaches that no one can 

 ascend to the top of Ararat. When Prof. Bryce told the 

 Archimandrite of the district that he had been to the 

 summit the old man only smiled a sweet, sad, pitying 

 smile, and sajd it was impossible. 



The more ;modern history of the chemical elements 

 warns us against dogmatising concerning the nature of 

 these bodies. Potash and soda were classed among the 

 elements until the year 1807. Water was for ages re- 

 garded as elementary; Cavendish first taught us that 

 the long-cherished tradition was false. 



The problem of the nature of the elements is one 

 which requires the use of the imagination ; it is a pro- 

 blem in endeavouring to solve which we are very ready 

 to give the reins to this faculty, or rather to allow the lower 

 power of fancy to usurp the place of the more divine 

 imagination — and thus we run riot. The naturalist who 

 approaches the investigation presented by the chemical 

 elements had need to learn the scientific use of the 

 imagination. 



Many years ago an hypothesis was started by Prout 

 to the effect that the elements are all compounds of 

 hydrogen, that hydrogen is the primary form of matter, 

 and that the molecule of each element is composed of a 

 varying number of atoms of hydrogen. If this hypo- 

 thesis were correct the combining or atomic weights of 

 the elements would be simple multiples of the combining 

 or atomic weight of hydrogen, i.e., multiples of I. The 

 experiments of Dumas lent support to the hypothesis 

 of Prout, but the later and more exact researches of Stas 

 negatived the idea. 



Stas showed, in a wonderful series of investigations, 

 that the atomic weights of the elements are not simple 

 multiples of i, nor of |, as Dumas had supposed, but 

 that they are fractional numbers. Stas further showed 

 that the same number, as representing the atomic weight 

 of a given element, is obtained by different processes of 

 investigation. 



But may not Prout' s hypothesis have some truth 

 underlying it ? Are the elements really elementary ? 

 Stas' s researches do not answer this question. W^e may 

 put the general question in two forms. Are the elements 

 compounds, in varying proportions, of a few simple 

 bodies? or, Are the elements compounds, in varying 

 proportions, of one primary form of matter ? Let us 

 look at these questions in succession — and first we may 

 frame the hypothesis that the elements are compounds 

 of a few simple bodies. 



In order to learn what are the general properties ex- 

 hibited by a series of bodies all of which are compounds, 



