188 Notices respecting Neiv Books. 



and many useful hints are given regarding the choice of the most 

 suitable type of apparatus. Chapter III. is devoted to the Pre- 

 paration Eoom and the Small Lecture Eoom, and deals with such 

 matters as the setting up of apparatus for use in the lecture- 

 theatre, the construction of various stands, supports and clamps, 

 gas-burners, oil and spirit lamps and electric heating appliances, 

 joints in glass and metal tubes and pipes, and in electric cables, 

 rheostats, driving belts and cords, and the care of apparatus 

 generally. Chapter IV., which is a comparatively short one, deals 

 with instrument cupboards, inventories of apparatus, the use of 

 the slide-rule and planimeter, and the preparation of lantern- 

 slides. Chapter V. fills nearly one-half of the book, and by the 

 majority of readers will probably be regarded as the most 

 important, since it deals with the workshop and its appliances. 

 The various methods of working in wood, metal and glass, lac- 

 quering, soldering, cementing, and kindred processes, all receive 

 due attention. Not the least striking feature of this chapter is 

 the extraordinary wealth of illustration, not only the tools them- 

 selves but also the methods of handling them being very carefully 

 and clearly illustrated ; this chapter alone, in fact, contains no 

 fewer than 1023 illustrations, the quality of which leaves nothing 

 to be desired. 



We have to congratulate Dr. Lehmann on the successful way 

 in which he has accomplished this part of his arduous task, and 

 have little doubt that his efforts will be gratefully appreciated by 

 all connected with the teaching of physics. The somewhat long 

 preface, in which he defends the educational value of Physics, and 

 criticises various suggestions regarding the way in which the sub- 

 ject should be taught, will also be found of considerable interest. 

 A portrait of the original author of the book — Dr. J. Prick — forms 

 a frontispiece to the volume. 



We are sorry to note that the book is printed in Gothic type — 

 so trying to most readers, but particularly annoying to foreigners ; 

 and we cannot but consider this — in a scientific work, at any rate — 

 as a most regrettable mistake. 



11 Radio. Di Augusto Bighi. Bologna : IS". Zanichelli. 1904. 

 (Attualita Scientifiche, No. 6.) Pp. 68. 



No simpler or more interesting account of the properties of 

 radium could be wished for than that which Prof. Eighi gives us 

 in this small booklet of 68 pages, which forms No. 6 of the series 

 known as Attualita ScientificJie. 



11 Selenio. Di Lavoeo Amaduzzi. Bologna : N. Zanichelli. 

 1904. (Attualita Scientifiche, No. 7.) Pp. viii + 142. 



The remarkable properties of selenium have given rise to a very 

 large number of researches, and have also served to stimulate the 

 mind of the inventor, who saw great practical possibilities in them. 

 If we except photo-telephony, the dreams of the inventor*still 



