and Laboratory Methods. 



2235 



J If !1^^^ 



Elementary Medical Micro-Technique for Physicians and 

 Others Interested in the Microscope. 



Copyrighted. 



XIV. SIMPLE PATHOLOGICAL TECHNIQUE.— Continued. 



Paraffin Embedding. This method of embedding offers special advantages 

 in that when the object in embedded it is not necessary to store it in alcohol or wet 

 it or the knife when sectioning it. Furthermore, much thinner sections may be 

 cut. Fix the specimen in Carnoy's fluid and transfer the specimen to absolute 

 alcohol, the same as previously described. Transfer the specimen from abso- 

 lute alcohol, removing the ad- 

 herent alcohol with filter paper, 

 to anilin oil until it becomes very 

 clear and sinks. Wipe off the 

 anilin oil and put the specimen 

 in xylol ten to twenty minutes. 

 Transfer to xylol, in which paraf- 

 fin of 43° centigrade has been dis- 

 solved to saturation, for an hour, 

 after which it should be placed 

 for two hours in melted paraffin 

 of 54° centigrade, which should 

 be kept in a paraffin bath or oveni< 

 at the lowest temperature at which 

 the paraffin will remain melted. 

 It is now ready to embed. Wrap 

 a piece of letter paper around a 

 homeopathic vial or block of wood that is larger than the specimen so that 

 the paper projects about an inch, making a cup of this depth. Pour full of the 

 melted paraffin, and with a warmed forcep rapidly transfer the specimen to the cup, 

 arranging it with the side to be cut towards the bottom. Blow on the paraffin 

 and when it has filmed over immerse it in cold water to harden, after which the 

 paper may be removed, the block taken from the bottle and clamped in the 

 microtome holder, the excess of paraffin from the deep cell affording a good 

 holding place. Set the knife to cut at right angles to the specimen. Trim the 

 paraffin block square so that one of the straight edges will be presented to the 

 knife. Cut dry. The sections should range from six to twelve microns in 

 thickness. Transfer the sections to xylol to remove the paraffin, then to alco- 

 hol to remove the xylol, then to water, after which they may be stained and 

 mounted the same as celloidin sections. 



Staining on the slide is a much better method of handling paraffin sections, 

 as it reduces to the minimum the loss of cells that is Ukely to occur in the watch- 

 glass method after the supporting paraffin is removed. 



Paraffin or Water Bath. 



