126 



THE ART OF MAKING MICROSCOPE SLIDES 



Defects 



Table 2 



DEFECTS APPEARING IN SECTIONS DURING COURSE OF MOUNTING 



Defect 



Cause 



Remedy 



Method of prevention 



Sections appear 

 wrinkled 



Sections have 

 bubbles under 

 them 



1. Blunt knife used for 1. None 

 cutting 



2. Water used for flat- 2. None 

 tening too hot, so 



that folds in sec- 

 tions fused into 

 position 



3. Sections unable to 3. None 

 expand sufficiently: 



(a) because water 

 used for flattening 

 too cold 



(b) because area of 

 water too small 



1. Sections insuffi- 

 ciently flattened, 

 so that air is 

 trapped 



2. Air dissolved in 

 water used for 

 flattening has come 

 out and is trapped 

 under sections in 

 drying 



1. Sharpen knife and 

 cut new sections 



2. Watch temperature 

 of water used for 

 flattening 



3(a) Watch tempera- 

 ture of water used 

 for flattening 

 (b) Make sure that 

 slide is clean, so 

 that water flows 

 uniformly over it 



Sections fall 1. Wax melted in 



off slide flattening 



1. If sections still wet, 

 reflood slide with 

 water and reheat to 

 complete flattening 



2. If sections still wet, 

 reflood slide with 

 water, work out 

 bubbles, and reheat 

 to complete flatten- 

 ing 



1. None 



1. Check flatness 

 sections before 

 draining slide 



of 



2. Slide greasy 2. 



3. Alkaline reagents 3. 

 dissolve albumen 

 adhesive. (Sections 

 start to work loose 



in course of staining 

 or dehydrating) 



4. Sections not flat- 

 tened into perfect 

 contact with slide 



None 



Treat slides with 

 Claoue's solution 

 (Chapter 28, V 21.) 



4. None 



2. Use air-free (boiled) 

 water for flattening 

 Drain slide thor- 

 oughly and blot off 

 excess moisture. 

 Squeeze sections to 

 slide 



1. Watch temperature 

 of water used for 

 flattening 



2. Use clean slides 



3. See Chapter 28. V 

 21 for other section 

 adhesives not 

 alkali-sensitive 



with an oil-immersion lens, the oil will dis- 

 solve a portion of the balsam which will 

 be found very difficult to remove either 

 from the surface of the coverslip or from 

 the front lens of the immersion objective. 

 The slide cannot be cleaned until it is 

 thoroughly dried and if it has been 

 mounted in a solution of resin, it will re- 

 quire several days on a hot plate or ^veeks 



4. Sometimes caused 

 by swelling of sec- 

 tions which causes 

 center to lift. 

 Squeeze sections to 

 slide and dry as 

 rapidly as possible 



at room temperature before the solvent 

 has been removed. When, however, it is' 

 finally dried, which is when the resin on 

 the edge can be cracked, the surface resin 

 should be removed carefully with a blunt 

 knife and the slide left overnight. If on 

 examination the freshly cut edge is then 

 found to be sticky, it is evident that more 

 solvent has moved out and that the slide 



