A REVIEW OF THE GOLGI METHOD. 155 



" This is not the place to lay stress upon the value of the 

 results which can be attained by means of this method. The 

 figures accompanying this work demonstrate it sufficiently. They 

 display the forms to be observed in the preparations with a fine- 

 ness not only not exaggerated, but inferior to the natural object. 

 I will here only bring forward the disadvantages of the method, 

 in order to give the means by which they are to be avoided. The 

 long time between the placing of the pieces in bichromate, and 

 the appearance of the reaction (it not infrequently happens that, 

 in consequence of this, the pieces are forgotten), the uncertainty 

 about the extremely variable time required to reach the proper 

 hardening, the different conditions in which individual layers of 

 the same piece are found, all these are disadvantages whose 

 removal would be desirable. 



" I have sought by expedients to change my method in one 

 way or another in order to secure greater certainty and accuracy in 

 the results. Among the means tried by me I present the following 

 which have yielded me a certain advantage. 



" («) Itijections of bichromate (solution to 2)4 percent.)* It 

 must be abundantly and constantly appfied so that the whole 

 parenchyma of the part to be investigated is fully and uniformly 

 penetrated by the hardening fluid. The fixation of the elements 

 by the reagent, where possible, before the slightest post-mortem 

 change can take place is of the highest importance in securing a 

 very delicate reaction. The action of the injection consists prin- 

 cipally in giving a uniform hardening, furthermore in preventing, 

 very likely, a slight post-mortem change in the interior of the 

 piece, and finally in abbreviating the sojourn in bichromate. 



" If I may draw a conclusion from some especially successful 

 reactions accomplished in this way, I must declare that the injec- 

 tion is in these various respects actually of considerable advantage. 

 Some other experiments, not yet very extended, have convinced 

 me that a favourable influence is exerted in the same way by 

 injecting, not a simple solution of bichromate, but one with gela- 

 tine added (2^ percent, bichromate, 100 c.c. ; dry gelatine, 

 which is dissolved in the usual way, 5 to 6 grams). This proce- 



* A stronger solution would probably be better, inasmuch as it undergoes 

 dilution in the tissue. — Author. 



