294 



SCIENCE. 



[Vol. VII., No. 164 



authority which would reduce it to the level of a 

 municipal board?" It may be safe to say, that, 

 until the English house of commons does consent 

 to divide its authority with some kind of a legis- 

 lative body in which the Englishmen who happen 

 to live in Canada and Australia shall have a voice, 

 every scheme for an 1 Oceana ' will prove ' chi- 

 merical and absurd.' 



MINOR BOOK NOTICES. 



New theories of matter and force. By William Barlow. 

 London, Sampson Low dt Co., 1885. 8°. 



Most theorists, in seeking to escape from the 

 difficulties in the way of an adequate conception 

 of the luminiferous ether, would hesitate to em- 

 brace a theory which involved either the denial of 

 the conservation of matter or the acceptance of 

 the emission theory of light ; and yet the author 

 of ' New theories of matter and force ' has no 

 craven fear of either or both of these conclusions. 

 Ordinary matter, he conceives, is a mixture of two 

 hypothetical ethers in a highly condensed state. 

 The properties of these ethers are peculiar. Both 

 have inertia, and, when unrestrained, expand in- 

 definitely like gases. One is more compressible 

 than the other, and cohesion in each is propor- 

 tioned to the density. To avoid all appearance of 

 action at a distance, this cohesion is not supposed 

 to be an attraction, but rather a clinging-together 

 of contiguous particles. This seems to require 

 these ethers to be continuous : but this is no 

 serious embarrassment to our author, who finds 

 no difficulty in reconciling perfect continuity of 

 substance with any desired degree of compressi- 

 bility. Owing to the diminution of the cohesion 

 with the density, these ethers have the remarka- 

 ble property that the expansive force increases as 

 the volume becomes greater. By means of these 

 two ethers we have the fundamental machinery 

 for the complete explanation of matter, gravita- 

 tion, light, heat, and electricity. The greater part 

 of the book is devoted to the application of the 

 theory throughout the whole realm of physics, 

 supplementary hypotheses being courageously in- 

 troduced when necessary. The main phenomena of 

 light are explained by a combination of the wave 

 and emission theories, as interpreted in the light 

 of two ethers. It is much to be regretted that the 

 author, before publishing his theory, did not sub- 

 ject it to a scrutiny at least as rigid as that which 

 led him to reject the accepted views. The scien- 

 tific imagination has an important use when 

 stimulated by knowledge and guided by reason ; 

 but before we lightly cast aside those theories 

 which are the result of the most profound 



thought, not of one mind, but of many, and 

 which have been slowly elaborating during patient 

 years, and set up in their stead our own brief con- 

 ceits, we may well pause and consider. 



The determ ination of rock-forming minerals. By Dr. Eugen 

 Hussak. Translated by Dr. E. G. Smith. New York, 

 Wiley, 1886. 1(3°. 



This is a work of which we cannot speak 

 favorably. Dr. Smith's evident lack of acquaint- 

 ance, both theoretical and practical, with the sub- 

 ject, has compelled him to make a close literal 

 translation from the original ; and, as would be 

 expected, numerous errors have thus crept in, in 

 addition to the many in the original. The whole 

 spirit of the German language is such that close 

 translations of technical works are rarely happy 

 in their results — certainly never, except when 

 one is most thoroughly familiar with both the 

 language and the subject under consideration. 

 It is very much to be doubted whether Dr. Smith 

 possesses either of these qualifications ; otherwise 

 he would never have made such errors as 4 the 

 entrance face of the light ' (eintrittsjlache) for 

 'plane of incidence,' and ' shell-formed' (schalen- 

 fdrmig) for ' zonal.' 



Along Alaska's great river. By Frederick Schwatka. 

 New York, Cassell, 1885. 8°. 



This excellently illustrated volume describes 

 the journey of Lieutenant Schwatka's exploring- 

 party from Portland, Ore., through the beautiful 

 inland passage along the north-west coast of 

 America, as far as Sitka in Alaska, thence over- 

 land to the head waters of the Yukon River, 

 which was explored with considerable accuracy 

 by his expedition as far as Fort Yukon. Schwat- 

 ka's raft -journey down the Yukon, and his 

 explorations in that region, have been often re- 

 ferred to in these columns. Capt. C. W. Ray- 

 mond, of the engineer corps of the army, had 

 surveyed and charted the Yukon River from 

 Fort Yukon to its mouth, about a thousand miles, 

 as early as 1869, and Schwatka pays a deserved 

 tribute to the accuracy of that officer's work. In 

 fact, the large chart of reference accompanying 

 the volume appears to be a reduced copy of Ray- 

 mond's chart, which is said to be the best in ex- 

 istence of that part of the great river. It is to be 

 regretted thai Schwatka's time for this explora- 

 tion was limited to one short summer, and that 

 his arrival at St. Michael's had to be so arranged 

 as to anticipate the departure of the last vessel 

 going south from that point in the fall. Otherwise 

 it is almost certain thai he would have explored 

 a much wider region, thus adding much to our 

 knowledge of thai almost unknown American 

 territory. 



