January 23, 1885.] 



SCIENCE. 



77 



to incorporate in this one the new material that, 

 as he tells us, he has prepared for a continua- 

 tion of his discussion. This new material is to 

 appear soon in another form ; and, until it ap- 

 pears, we must postpone any detailed criticism 

 in these columns of our author's known views. 

 That the book contains much fair discussion 

 of theories, and a very readable collection of 

 facts, is plain enough ; and, on the other hand, 

 one need not dwell on the consideration, that, 

 in their present form, these lectures cannot be 

 considered as abreast with the advance of so 

 rapidly growing a study as this. We shall add 

 here only one criticism ; namely, that there is, 

 in this work, one obvious imperfection that has 

 especially to do with our author's principal 

 purpose itself. .Professor Chadbourne studies 

 instinct in animals that he may throw more 

 light on the place and relations of instinct in 

 man. But, just when he comes to speak of 

 human nature, his psychological foundation is 

 so antiquated, that all his learning helps us, 

 his readers, but a little way. It is the old 

 schematized and abstract ps} T chology that is in 

 his mind throughout, with its ' rational ' and 

 ' moral natures ' of man, with its more or less 

 complex scheme of subdivisions in each of 

 these ; natures,' and with its notion of an ab- 

 stractly defined hierarchy of human powers. 

 For very elementary instruction, not in psy- 

 chology as such, but in morals, this old psy- 

 chology will still do well enough, no doubt, as 

 a sort of rough working hypothesis ; but the 

 scheme is unreal, and modern psychology finds 

 little use for it. 



For this reason it is, that, when our author 

 draws an elaborate parallel between the func- 

 tions of the sense of obligation and those of 

 the instincts, we feel that the undoubted actual 

 likeness of these two sets of phenomena is 

 distorted in his description, for the sake of 

 fitting the facts to an a priori notion about 

 the ' higher spiritual nature ' of man . When 

 he gives us an elaborate diagram, representing 

 the place of the instincts among human facul- 

 ties, we feel that this diagram represents a 

 sort of stuffed soul, badly mounted, as it were, 

 and no living soul of man at all. When, 

 again, an argument for immortality peeps out 

 from behind our author's classification of 

 the belief in immortality as an instinctive 

 human belief; when, in fact, we are told that 

 one instinct ought to be as well founded as 

 another, and that the belief in immortality is as 

 much an instinct as is the instinct of an insect 

 to lay eggs in autumn, — we feel only a sense of 

 vexation that an ill-conducted analysis of hu- 

 man nature, accepted by our author from tradi- 



tion, should be used by him for such a purpose 

 in a scientific course of lectures. Why mix to- 

 gether utterly separate lines of consideration ? 

 Our belief in the real goodness of things, and 

 in the worth of life, gains no whit, and can 

 only lose force, by being confused with investi- 

 gations into external physical phenomena, or 

 even into the laws of the sequence of mental 

 states. That tradition has long since sanc- 

 tioned this confusion is no justification for it 

 here. . 



RECENT TECHNICAL BOOKS. 



Cain's algebra contains two entirely dis- 

 tinct essaj's. In the first of them, with the 

 hope of making the treatment of negative 

 quantities clear to the student of elementaiy 

 mathematics, the author represents real quanti- 

 ties in the usual way, — by lengths laid off upon 

 a straight line, towards the right from a fixed 

 origin on the line if the quantities are positive, 

 towards the left if they are negative, — and 

 develops successively the rules for algebraic ad- 

 dition, subtraction, multiplication, and divis- 

 ion, by the help of this concrete conception. 

 The rules thus obtained are then shown to be 

 generally applicable to all problems, whether 

 the difference between positive and negative 

 quantities in them is one of opposition in direc- 

 tion or not ; and the essa} 7 closes with some 

 remarks on the general^ of formulas of trig- 

 onometry and analytic geometry proved for a 

 single case. 



In the second essa}-, Professor Cain describes 

 some methods common to all sciences of rea- 

 soning, compares and illustrates by examples 

 the analytical and synthetical methods for the 

 solution of problems, and finally discusses a 

 few examples in finding the equation of loci, 

 where some solutions are lost in the course of 

 the work, or where some strange ones are in- 

 troduced. The distance of the point P' from 

 the point P seems to be written indifferently 

 PP' or P'P. The little book would doubtless 

 prove interesting and suggestive to airy student 



Symbolic algebra, or the algebra of algebraic numbers, 

 together with critical notes on the methods of reasoning em- 

 ployed in geometry. By Prof. W. Cain, C.E. New York, Van 

 Nostrand, 1884. (Van Nostrand's sc. ser., No. 73.) 131 p. IS . 



Testing -machines : their history, construction, and use. By 

 Arthur V. Abbott. New York, Van Nostrand, 18*S4. (Van 

 Nostrand's sc. ser., No. 74.) 190 p. 24°. 



Stadia surveying: the theory of stadia measurements, accom- 

 panied by tables for the reduction of stadia field-observations. 

 By Arthur Winslow. New York, 'Van Nostrand, 18S4. (Van 

 Nostrand's sc. ser., No. 77.) 148 p. 24°. 



The steam-engine indicator, etc. By TV. B. Le Van. New 

 York, Van Nostrand, 1S84. (Van Nostrand's sc. ser., No. 7S.) 

 169 p. 24°. 



