484 



NA TURE 



[OcTOIiER 2 I, tC,09 



though it can hardly compare in importance with 

 some of its brilliant predecessors. 



Prof. Pillsbury, like his former teacher, Prof. 

 Titchener, in a still more recent book, defines atten- 

 tion as " an increased clearness and prominence of 

 some one idea, sensation, or object." His first thir- 

 teen chapters are devoted to the illustration of this 

 description from general psychological processes; to 

 an analysis of the part played by attention in the 

 phenomena of perception and ideation, of memory, 

 action, reason, emotion, and the self; and to a study 

 of the conditions which determine the incidence of 

 attention. With regard to the latter, he contends for 

 a simplification of current classifications. The 

 " forms " of attention generally recognised are dis- 

 tinguished either by the presence of elements (such as 

 strain sensations) which are extraneous to the sen- 

 sation-process or else by the nature of the objects to 

 which attention is directed. There is really onlv one 

 kind of attention, though the conditions of its emer- 

 gence are two-fold. These are : objective conditions 

 which consist in characteristics of the stimulus, such 

 as its intensity, extent and duration ; and subjective 

 conditions, such as the momentarv mood and past 

 experiences of the individual. Finally, it must be 

 noted that these conditions never or rarelv appear in 

 entire separation. 



The later chapters are mainly given to theories of 

 attention, grouped as physiological theories, theories 

 that treat attention as a phase of mental activity, and 

 theories that seek in some particular feature or accom- 

 paniment of the attention-process the cause of the 

 predominant " clearness " of certain sensations and 

 ideas. .As a critic of preceding theories Prof. Pills- 

 bury's best work is his interesting and useful treat- 

 ment of apperception. His own theory is a physio- 

 logical one, and assumes " localisation " of the activity 

 of attention in the so-called anterior association centre 

 of Flechsig. By a kind of "drainage," for which 

 there is e.xperimental evidence, the discharge through 

 a given neuronic system may be heightened bv the 

 coexistence of less energetic discharges in connected 

 systems, or depressed by a still more energetic dis- 

 charge in such a system. The association centre pro- 

 vides lines of irradiation along which reinforcement and 

 inhibition may in this way spread from one sensory 

 centre to another. By such a concept Prof. Pillsbury 

 believes that the determination of attention, both by 

 strong stimuli and by past experience, can be explained 

 in accordance with the postulate of psychophysical 

 parallelism, and without the hypothesis of an un- 

 verifiable agent " that stands behind consciousness." 



The book ends with a chapter on pedagogical appli- 

 cations. The author attacks the doctrine that makes 

 "interest the measure of what shall be taught " to a 

 child. He argues for the use of " social pressure," 

 and the appeal to duty in education. " Thev are just 

 as important as the conditions which we ordinarily call 

 interest in governing attention, and it is quite as 

 justifiable to make use of them in practice." This 

 warning of a psychologist against making education 

 " soft " is not untimely, although (owing to the 

 lamentable ambiguity of the word " interest ") he is 

 XO. 2086, VOL. Si] 



condemning a theory of teaching which no responsible 

 pedagogical writer — at least in this country — would 

 dream of defending. 



In addition to a good index the book contains a 

 bibliography of the subject for which the student will 

 be grateful. 



TABLES FOR MATHEMATICIAXS .-l.VD 



PHYSICISTS. 



(i) f'ivc-figtirc Logaritlimic and oth.cr Tables. Bv 



Frank Castle. Pp. 58. (London : Macmillan and 



Co., Ltd., 1909.) Price is. 

 (2) Taschenbuch jiir Mathcmatiher uiid Physikcr. 



1 Jahrgang, 1909. By Fcli.x .\uerbach. Pp. xliv + 



450. (Leipzig : B. G. Teubner, 1909.) Price 6 



marks, 

 (i) 1\ ,1 R. CASTLE is well known as the author of 



^ ' ^ a series of elementary text-books on • 

 mathematics. He now gives us a new set of five- 

 figure mathematical tables. So many tables of this 

 sort have appeared of late years that innovation in 

 this field is rather difficult. Mr. Castle's tables are 

 very similar in contents to Dale's five-figure tables, 

 with the advanced functions cut out. One hapnv 

 alteration is that, in the early part of the table of 

 logarithms, mean differences are calculated for every 

 five entries instead of for every ten. This renders 

 possible the use of mean differences in all parts of 

 the table without loss of accuracy. .Another good 

 point is a table of degrees and circular functions for 

 equal intervals of radian measure; this should be 

 most valuable for advanced work. 



On the other hand, there seems a needless amount 

 of repetition in printing. Thus the table of sines is 

 printed separate from the table of cosines, although 

 the one table is merely the other read backwards. The 

 same holds of tangents and cotangents, secants and 

 cosecants. It may be argued that this makes the 

 tables easier to handle for readers with little theo- 

 retical knowledge, but it seems doubtful whether it 

 will not encourage rather than check the common 

 fault of adding, instead of subtracting, differences for 

 the cosine, cotangent, and cosecant. 



.\ more serious defect is the omission, from the 

 table of cube roots, of the cube roots of numbers fron'i 

 100 to 1000. This means that the present tables 

 cannot be used to find rapidly the cube root of, say, 



(2) -A pocket-book of reference for mathematicians 

 and physicists will strike most mathematical readers, 

 at all events in this country, as a novelty. Such a 

 pocket-book was recently brought out in Germany 

 bv Dr. Feli.x .Auerbach, working in collaboration with 

 Drs. Knopf, Liebmann, and Wolffing. Facing the 

 title-page is a portrait of Lord Kelvin, and the volume 

 opens with a notice of his life and work. 



It is intended that this shall be an annual publica- 

 tion. For this reason. Dr. Auerbach tells us in his 

 preface, many matters have been only lightly touched 

 upon, or even omitted altogether, in the hope that 

 further details concerning them may be included in 

 a later issue. 



