33 



SCIENTIFIC NEWS. 



[July 13, 1888. 



the opposite side of the cavern and view me from another 

 quarter. Whether it possessed that peculiar, hoarse, 

 chattering note common to most of the family, I was at 

 a loss to know, until, by accident, I moved slightly, when, 

 with a sudden movement, it dashed across the open 

 space, plunged into the bushes, and descended gradually 

 to the bottom of the valley, scolding to itself all 

 the way. During the next half-hour a dozen or more 

 individuals were heard, and many others were un- 

 doubtedly in the vicinity. Descending now some fifty feet 

 to a shelf which runs the entire length of the rocks, I 

 followed it for some distance, and was pleased to note a 

 number of the birds in question clinging to the walls, 

 darting into the air and seizing insects in the manner of 

 the tyrannidse, disappearing from view for a time, while 

 they searched the interior of some dark retreat, and appear- 

 ing again often where least expected ; on one occasion I 

 observed one enter an orifice in the rocks some twenty 

 feet distant, and, while watching closely for its return, 

 was amused to have it dart from a hole directly before 

 my face. The bird was fully as surprised as myself, 

 and considerably more frightened, for it dashed around -a 

 neighbouring blufFand went some distance down the cliffs. 

 This closed my experience with them until later in the 

 season, when I again met a few in the vicinity of 

 Comanche Peak, in Hood country, and again, a week 

 later, on Paluxy Creek ; but it was now late in the fall, and 

 their voice had lost mnch of its melody and richness. 

 They are never, I believe, to be found at any great 

 distance from the gorges and cliffs, which are their 

 favourite haunts, and while the beauty of other localities 

 is enriched by the songs of hundreds of musical little 

 throats, it is reserved for the present species to lift in 

 part and to cheer the gloom which for ever overshadows 

 some of Nature's mightiest and grandest works. — 

 Scientific American. 



l£ri>feto;S* 



Notes on Inorganic Evolution. By E. A. Ridsdale. 

 London : H. K. Lewis. 

 If evolution is in truth a primary law of the universe, 

 we should be able trace it, not merely in stars and in 

 living beings, but in the materials of which both stars 

 and living beings consist — that is, in chemical compounds, 

 or, perhaps, even in those elements from which such 

 compounds are put together. Just as at present scientific 

 men are seeking to trace out among organisms the 

 counterpart of the periodic law of Newlands and Men- 

 deleeff, so they are also searching for evidences of evolu- 

 tion in the chemical sphere. Now, here Mr. Ridsdale 

 seems to us to have thrown a new and valuable light 

 upon the question. It is generally admitted that the 

 flora and fauna of the world consist of those plants and 

 animals which have survived as being most fully in 

 harmony with the totality of the circumstances among 

 which they are placed. But can we find anything not 

 identical but corresponding in the mineral world ? Mr. 

 Ridsdale tells us that the ruling principle here is the 

 " survival of the most inert." Says the author : " When 

 any new compound is formed, it is produced by reason 

 of the greater affinity of the constituents of the new 

 compound for each other than for the constituents of the 

 older bodies of which they formerly made a part. . . . 

 Bodies whose constituents have little affinity for each 

 other tend to be broken up, and those compounded with 

 stronger affinities to persist." Hence bodies held to- 



gether by strong affinities will accumulate, whilst those 

 held together by feeble affinities will gradually disappear. 

 But it is further remarked that bodies having for each 

 other very strong affinities may have still stronger ones 

 for some other body or bodies, so that a body thus com- 

 pounded may have in the long run a smaller chance of 

 remaining unchanged than a body less strongly held to- 

 gether with weaker elemental affinities. Hence the body 

 which is, as a whole, the most inert, is most likely to 

 survive. The author shows — what will scarcely be con- 

 troverted — that any such gradual " selection of the most 

 inert " must have been exceedingly slow. He thinks 

 that the evidence to be found is, upon the whole, favour- 

 able to this supposition. He reminds us that there 

 is a constant tendency for barium salts to become 

 sulphates ; -magnesium and aluminium salts to form oxides 

 and silicates ; silver salts, chlorides ; lead salts, sulphides, 

 etc. The inert salt, when once formed, except under 

 abnormal conditions, remains, whilst any other salt, how 

 often so ever it may be formed, is sooner or later broken 

 up. 



From these facts — for so far, at least, what he advances 

 may be accepted as fact — certain striking conclusions 

 follow as being, though not demonstrated, yet analogically 

 probable. What are those bodies which we call simple 

 or elemental ? Are they not possibly — even probably — 

 compounds which under the existing conditions of things 

 are, as wholes, more inert than any other class of bodies, 

 ar.d thus persist ? Says Mr. Ridsdale very happily : — 

 " Every chemical body is ' elemental ' to some set of con- 

 ditions, or it could not exist, and an element may only 

 be a body stable under more extreme conditions than 

 usual " — in other words, more inert. Pointing out that 

 in any group of the elements, the most active are those 

 with the lowest atomic weights, and vice versa {e.g., 

 fluorine as compared with iodine) he suggests as possible 

 that in each group of the elements those with the lowest 

 atomic weights were formed first, and then those with 

 higher atomic weights. Here, as the author intimates, 

 we find ourselves running, not merely parallel to the 

 law of Newlands and Mendeleeff, but to the more recent 

 work of Mr. Crookes, F.R.S. On comparing the workings 

 of this principle of the " survival of the most inert " with 

 those of organic evolution, we can scarcely fail to find a 

 number of very instructive resemblances. Many more 

 passages in this pamphlet, brief but pregnant, deserve 

 careful consideration. But we will merely quote the 

 author's concluding remarks : — " That the various forms 

 of matter are not radically distinct has longbeen supposed ; 

 that the early condition of the universe was fiery and 

 gaseous, has almost passed the domain of theory ; that 

 our solar system at least is gradually tending to an inert 

 or dead condition, is generally believed. Any hy- 

 pothesis that can correct and explain such varied beliefs 

 without running counter to evidence is worthy, at any 

 rate, of a hearing." 



Journal of the Franklin Institute of the' State of Penn- 

 sylvania. Vol. cxxv., No. 6. June, 18S8. 

 By far the most interesting paper in this issue is the 

 report on water-spouts off the Atlantic coast during 

 January and February of the present year, drawn up by 

 Mr. Everett Hayden. These alarming and sometimes 

 dangerous phenomena have been unusually plentiful, 

 both on land and sea. Our readers will remember that 

 two water-spouts — perhaps the German term " Wolken- 

 bruch," or, as it may be rendered, " cloud-burst, is mort 



