CLEANING SLIDES AND COVER-GLASSES [Cn. X 



32nds. 

 1 .0312 

 3 .0937 

 5 .1562 

 7 .2187 

 9 .2812 

 11 .3437 

 13.4062 

 15.4687 



1-8 .125 

 1-4. .2 5 

 3-8 .375 

 ICths. 

 1 .0625 

 3 .1875 

 5 .3125 

 7 .4375 



FIG. 1 88. MICROMETER CALIPERS FOR MEASURING 

 THE THICKNESS OF SLIDES AND COVER-GLASSES. 



(From the Catalogue of the Brown & Sharpe Manu- 

 facturing Company). 



alcohol added. The 

 covers remain in this 

 until needed. In wip- 

 ing use the precau- 

 tions given with slides 



(49)- 



Test for the proper 

 cleanliness as for slides 

 ( 490), and remember 

 the advantage of heat- 

 ing the cover-glass in 

 a Bunsen or alcohol 

 flame to render it cap- 

 able of receiving a smooth and even film of blood or other aqueous 

 liquid. 



494. Cleaning large cover-glasses. For serial sections and 

 especially large sections, large 

 quadrangular covers are used. 

 These are to be put one by one 

 into a cleaning mixture as for 

 the smaller covers and treated 

 in every way the same. In wip- 

 ing them one may proceed as for 

 the small covers, but special 

 care is necessary to avoid break- 

 ing them. It is desirable that 

 these large covers should be 

 thin not over 0.15-0.20 mm., 

 otherwise high objectives can- 



FIG. 189. MEASURER FOR SLIDES AND 

 COVER-GLASSES. 



not be used in studying the 

 preparations. 



495. Measuring the thick- 

 ness of cover-glasses. It is of 

 great advantage to know the ex- 

 act thickness of the cover-glass 

 on an object; for, (a) in study- 



from the figure in Zeiss 

 Catalogue). 



Cover A cover-glass between the jaws (f) 



J Jaws between which the object to 

 be measured is placed. 



H Hand which points to the gradua- 

 tions on the face indicating the fractions 

 of a millimeter or inch that represents the 

 thickness of the object between the jaws. 



L Lever by which the jaws are opened 

 to receive the object. 



