XXIII, 2. Huber: Method of preparing large Nurabers of Sections. 193 



or, in case the tray contains the water -dextrin Solution above men- 

 tioned , a glass-plate thoroughly cleaned is placed into this. The 

 ribbons of paraffin sections are now cut to the necessary lengtli and 

 transferred with needles or brush to the surface of the water or 

 the water- dextrin Solution and arranged as desired. The water or 

 the water -dextrin Solution is now heated by means of a flarae until 

 it becomes sufficiently warmed to flatten out perfectly the paraffin 

 sections. The flame is removed when this is accomplished. The 

 fiattened ribbons are now arranged as close together as possible 

 and a hot needle inserted at several places between the contiguous 

 borders of the several ribbons. This melts the paraffin over a small 

 area and on cooling leaves the ribbons united at points where the 

 hot needle has been inserted. 



The water or the water -dextrin Solution may now be allowed 

 to drain off through the outfiow, when the ribbons of flattened 

 paraffin sections will settle on the glass-plate. With a little exercise 

 of care, however, the glass-plate may, after the flattening of the 

 sections, be lifted from one end and drawn from the water without 

 in the least disturbing the sections nor their arrangement; especially 

 is this true if the ribbons of paraffin have been joined together 

 with a hot needle as above suggested. This procedure is now 

 followed, as by this method the distilled water or the water- dextrin 

 Solution may be used over and over again , it being only necessary 

 to heat it a little from time to time to keep it sufficiently warmed 

 to cause the sections to flatten out properly. After removing the 

 plates from the water or water- dextrin Solution, the excess of water 

 is drained off and they are set aside, being placed horizontally until 

 the water evaporates. This may be accomplished at room tempe- 

 rature or may be hastened by placing the plates in a warm-oven 

 heated to about 35 "^ or 40". The plates are ready for the removal 

 of the paraffin as soon as the water has had time to evaporate. 

 Experience has shown that the 'S^Jq to ö'^Jq of the sugar- dextrin 

 Solution used contains enough of the sugar and dextrin to prevent 

 the sections from becoming too dry on evaporation of the water. 

 To melt the paraffin it is convenient to place the glass-plate, section 

 side up , on a warming plate heated from one end with a flame, 

 the end of the plate nearest the flame being supported by a glass 

 rod 8 mm to 10 mm in thickness ; this to equalize the temperature. 

 As soon as the paraffin surrounding the sections is melted the plate 

 is placed into xylol and is then trausferred to absolute alcohol. For 



Zeitschr. f. wiss. Mikroskopie. XXIII, 2. 13 



