BENTLEYj ON BOTANY. 313 



to be said of the production of every intelligeut physician, yet 

 we feel that so large a proportion of medical literature de- 

 voted to the exposition of disease is utterly worthless for 

 the want of microscopic investigation, that we are glad to be 

 able to notice a work in Avhich the microscope has been em- 

 ployed as a necessary instrument of research. In fact, no 

 class of diseases illustrate more fully the use of this instru- 

 ment than those which affect the kidney. It was not till 

 BoAvman, by the aid of the microscope, had elucidated the true 

 structure of the kidney, and pointed out the functions of its 

 different parts, that the full significance of Bright's discovery 

 of the relation betAveen the composition of the urine and the 

 morbid conditions of the kidney, began to be fully understood 

 and appreciated. Nor has microscopic investigation been 

 confined to the structure of the kidney or it might have been 

 more difficult to connect the living indications of diseased 

 structure Avith the nature of such structure obserAcd after 

 death ; but the microscope has been applied to the urinary 

 secretion, and this product constantly passing away is made 

 to indicate not only the diseased conditions of the kidney, 

 but their progress from hour to hour and day to day. It 

 will be, therefore, evident that those Avho attempt to treat 

 disease of the kidney Avithout the use of the microscope are 

 really practising in the dark, and, for all the good they are 

 likely to do, they are only on a par Avith any uninstructed 

 person Avho would undertake to treat disease without under- 

 standing its nature. Of course Dr. GoodfelloAv's book will 

 not teach those ignorant of the use of the microscope how to 

 employ it, but those already capable of using the instrument, 

 will find in his volume the points indicated in Avhich it be- 

 comes indispensable to the use of the medical man Avho AAashes 

 to understand the nature of the diseases he treats. 



A Manual of Botany. By Robert Bentley, F.L.S. 

 London : Churchill. 



After the valuable manuals of Lindley, Balfour, and Hen- 

 frey, the critic may be forgiven for asking. What need could 

 therebe for another ? We imagine that this is a question which 

 the publisher rather than the author ought to answer. If the 

 publisher, Avho is the great middle-man between the author 

 and the public, thinks that another manual of botany Avill 

 pay, then it is his business, and all the critic has to do is to 

 see that the public is likely to get its money's worth. Now, 



