728 A GUIDE FOR STUDENTS OF MICROTOMY 



the wax is too hard or the slope of the knife is not correct. If the wax 

 is hard, place 1 drop of soft wax on each side of the block and flatten it 

 out with a warm knife. Read carefully pp. 83 to 96. 



(37) The broad side of a block should be parallel to the knife. 



(38) Some people use miniature drums for rolling up the wax ribbon. 

 Laying them on a piece of foolscap does quite well. Avoid sticky paper. 

 If sections accidentally adhere you can often release them by cautiously 

 wetting the paper with 90 per cent, alcohol. 



(39) Before placing sections on a slide, write with a diamond pencil 

 the number of the slide and the material used. At a pinch, a glass wax- 

 pencil may be used instead. 



(40) If you have not used a diamond, it is always possible to tell on 

 which side of the slide the section lies, simply by slightly tilting the slide 

 and observing the shadow thrown on the other side of the glass. 



(41) For fixing and imbedding hard material read §§ 172 to 177. 



(42) Dioxan technique is much used nowadays. Dioxan is a cumula- 

 tive poison and should only be used in well-ventilated rooms. 



(43) For imbedding very small objects read § 157. 



(44) For making preparations of insects read methods in § 1188. 



