WITH THE MICROSCOPE. 



mistaken for fine nerve fibres the vessels have not been injected in 

 specimens which have been supposed to controvert my conclusions. 

 The mode of preparation I have advocated is not a mere hap-hazard 

 plan, but is the result of information derived from numerous experi- 

 mental observations made during the last fifteen years. Some have 

 endeavoured to throw doubts upon my conclusions by describing how 

 little they have themselves been able to see after the rough processes 

 they have followed. The stout denial often given to the existence of 

 a particular arrangement in too many instances, really means only 

 that the individual who makes it has never seen the appearance. 

 The only wonder is, that any one who has really earnestly studied, 

 should be able to persuade himself that he has seen all that has been 

 or all that can be seen. 



I cannot venture to hope that many facts I have observed in the 

 minute structure of the central and peripheral nervous system, will 

 be confirmed until the process adopted by me is followed by 

 others. It is true that my specimens can be shown to others ; but it 

 so happens that working men have but few opportunities of examin- 

 ing each other's specimens, and when an opportunity does occur, it 

 not unfrequently happens that time is not allowed to investigate 

 the specimens fairly. The consequence of this is, that working in 

 circles goes on to a terrible extent. Great labour is utterly wasted, 

 and there is but very slow progress compared with that which would 

 attend our efforts if observers generally were agreed upon the principles 

 upon which minute anatomical observations should be conducted. 

 Doubtless, every observer soon finds out valuable methods of detail 

 for himself which satisfy him, but as he will not be able in many 

 cases to communicate to others the practical details upon which his 

 success depends, it is often exceedingly difficult to ascertain the 

 real merits of any given process. Nevertheless, it is a question 

 capable of being settled most positively, whether nerves can be fol- 

 lowed in tissues which are impregnated with syrup, glycerine, or 

 some such medium, for a greater distance than when the same textures 

 are immersed in water, serum, vitreous, &c., and whether or not more 

 fibres and finer fibres can be seen in the former than in the latter 

 case. A simple experiment will convince any one that this is so, 

 and if observers would prepare small portions of the same tissue in 

 these two different media, and compare the results, they would, I am 

 sure, soon agree upon one principle of great importance in investigation. 

 It is mainly with the view of encouraging free discussion upon this most 

 important question, and in the hope that ere long some general pro- 

 cess of investigation may be followed, that I publish my own con- 

 clusions and describe somewhat minutely the process which I now 



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