304 



SCIENCE. 



[Vol. IX., No 216 



reiterated defence of the usefulness of the ' dealer ' 

 or middleman in the economical structure of soci- 

 ety might, but probably would not, have been 

 penned by any one but a commission-merchant. 

 As might be expected, the author's practical 

 training produces the best results in those parts of 

 the subject where a personal concern in affairs is 

 essential to a thorough imderstanding. His chap- 

 ters on banking, commerce, and credit are clear 

 and incisive. There is no striking novelty in 

 them, but the fresh and vigorous style clothes the 

 old ideas with a living interest. In his treatment 

 of the fundamental definitions and ^generally ac- 

 cepted principles of scientific economics, Mr. Dan- 

 son is in many respects rather original than convin- 

 cing. While deprecating the confusion that arises 

 from Ihe use of the same term in different mean- 

 ings, he defines 'profit' in an entirely novel man- 

 ner, and, on the strength of this, goes on to com- 

 bat the theories of profit that have been proposed 

 by economists who retain the old definitions. He 

 maintains that profit is earned only by risk : it is 

 therefore inseparable from capital. The manager 

 who conducts business on borrowed capital re- 

 ceives only wages ; for the lender risks the loss of 

 his capital, and the additional rate of (so-called) 

 interest he receives to cover the risk is really the 

 'profit.' On this theory, it is evident that Mr. 

 Danson would limit the terra 'interest' to the 

 remuneration for loans on which the security is 

 absolutely perfect, or, in general, to a purely hypo- 

 thetical quantity, and would use ' profit ' princi- 

 pally to denote the income of insurance compa- 

 nies. We doubt that economists generally will 

 follow him. 



' Rent ' is another term in respect to which our 

 author courts originality. He regrets the variety 

 of meanings assigned to the word, and proceeds 

 to mend matters by setting forth an entirely new 

 one. We shall not follow him in his career. 

 Ricardo will doubtless survive the latest sceptic's 

 assault. The result of our author's doctrine is 

 wrought into a radically conservative view of the 

 modern land-question. Henry George is neatly 

 annihilated by a demonstration of the fact that, 

 there is no such a thing as an ' unearned incre- 

 ment' in the value of land. The general treat- 

 ment of the land-question indicates a probability 

 that some of the profits, or rather ' wages,' of the 

 commission-merchant have found investment in 

 an English estate. 



On the labor and wages question, Mr. Danson 

 cleaves to the old school. The interests of labor 

 and capital are identical, and all that the laborers 

 have to do is to eschew trades-unions and become 

 millionnaires as soon as possible. Inspection-laws 

 for factories, like poor-laws, are inherently vicious. 



and, in general, laissez faire ; some of which 

 sentiments indicate that a Liverpool commission- 

 merchant feels under no necessity of advancing 

 merely because the rest of the world does. 



Wm. a. Dunning. 



SOME RECENT MINERALOGICAL TEXT- 

 BOOKS. 



Manual of mineralogy and petrography. By James D. 

 Dana. 4tli ed. New York, Wiley. 12°. 



The well-known manual of Professor Dana ap- 

 pears in much its former guise, but with such 

 alterations as are needful to keep it abreast of the 

 progress made in mineralogical and petrographioal 

 science during the nine years which have elapsed 

 since the publication of the third edition. The old 

 arrangement is preserved throughout, which will 

 prove acceptable to those who are already familiar 

 with the book. It is only intended for an ele- 

 mentary treatise, for the use of schools or of the 

 practical miner and geologist : hence the arrange- 

 ment of the species according to their principal 

 metallic base is advantageous. The full list of 

 American localities and the tables for determining 

 minerals are also valuable addenda. The. chapter 

 on rocks has undergone extensive changes. The 

 terms ' petrography ' and ' petrology ' are pre- 

 ferred to ' lithology,' which was formerly used. 

 The various grounds of classification are stated, 

 and the rocks divided into, 1°, calcareous ; 2°, 

 fragmental, not calcareous ; 3°, crystalline, not cal- 

 careous. The arrangement of the members of the 

 last class is much like that of Rosenbusch. The 

 banded and schistose varieties are classified with the 

 massive ones, but they are for the most part con- 

 sidered ' metamorphic,' by which term the writer 

 seems to imply that they are altered sediments. 

 The metamorphism of eruptive rocks into schists 

 seems hardly to have secured recognition. Alto- 

 gether the book is increased by only forty-three 

 pages, but its many improvements will secure it a 

 welcome among all teachers. 



Tables for the determination of common minerals. By 

 W. O. Crosby. Boston, J. A. Crosby. 8°. 



Professor Crosby's tables are intended to aid be- 

 ginners in the identification of the commoner min- 

 erals, chiefly by means of their more apparent 

 physical properties, and then to show them how 

 the determination may be confirmed by simple 

 chemical tests. The classification is, f, accord- 

 ing to lustre (metallic and non-metallic) : 2'', ac- 

 cording to the color of the metallic, and the streak 

 of the non-metallic minerals ; and, 3", according 

 to the hardness. In this way forty-one classes are 

 formed, which are further subdivided in the ana- 

 lytical key by specific gravity, texture, crystal 

 form, cleavage, etc. The method is the result of 



