PEE FACE. IX 



I have entirely re-arranged the contents of these three 

 chapters according- to a scheme worked out by him, thereby 

 effecting a great gain in clearness of exposition. I cannot 

 but acknowledge that the arrangement adopted in previous 

 editions resulted in something like a chaos ; whilst the new 

 arrangement may, I think, fairly claim to be natural, logical, 

 and easily comprehensible. By his advice, too, I have entirely 

 re-written the account of the bichromate of silver impregna- 

 tions of Grolgi ; the account as it now stands is, i believe, 

 the only complete one that has appeared in the English 

 language. 



I am under the greatest obligation to Professor van 

 Gehuchteii, as well as to Dr. Paul Mayer, for the generous 

 assistance which enables me to affirm that the important 

 subjects in question have been treated with all the requisite 

 accuracy and thoroughness. 



The essential feature of the first edition was that it was an 

 altogether exhaustive collection of all the methods of pre- 

 paration that had up to that time been recommended as 

 useful for the purposes of microscopic anatomy, and its 

 primary intention that of being a work of reference for the 

 instructed anatomist. Its character of a guide to the be- 

 ginner was secondary only. It contained, indeed, a general 

 introduction and much explanatory matter in the different 

 chapters, but, on the whole, the didactic matter bore but an 

 insufficient proportion to the historical matter. This has now 

 been rectified. It has come to pass that during the repeated 

 operations of revision to which the book has been subjected, 

 the explanatory and didactic element has been continually 

 increasing, whilst at the same time the historical element 

 has been continually diminishing diminishing, that is, in all 

 parts of the book relatively to the former element, and in 

 some parts absolutely (as may be seen, for instance, by com- 

 paring the number of formulas given in the chapters on 

 Carmine and Haamatoxyrm with the number given in former 

 editions) . On the one hand the book has been lightened by 



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