Sealing 



FLUID WHOLEMOUNTS — AQUEOUS TYPE 



25 



Cavity 



Gold size ring 



Drop of preservative 



Object 



10 



,^ 



Coverslip 



11 



Preservative 

 withdrawn 



12 



^_ 



Gold size 

 coat 



sealing 



13 



Asphalt varnish 

 ^^^finishing coat 



^^^ . 



14 



Figs. 9 to 14. Longitudinal section of a cavity slide showing successive stages in 

 the preparation of an aqueous wholemount. 9. Protective ring of gold size turned. 10. 

 Object placed in position in a large drop of preservative. 11. Coverslip held horizontally in con- 

 tact with preservative. 12. Coverslip lowered and preservative withdrawn between protective ring 

 and edge of coverslip. IS. Heavy sealing coat of gold size applied. I4. Finishing coat of asphalt 

 varnish applied over gold size. 



