MEMORANDA. 



109 



nut E the disc B, and with it the thin glass cover, may be 

 removed for the purpose of cleaning, or for attaching a fresh 

 cover in the case of Ijreakage. On moving the disc and cover 



ric .1 



^- 



FIC 



;\C^^rg^ 



aside, as shown in fig. 1, the object, with a sufficient supply 

 of water, can be readily introduced ; some care, however, is 

 required in doing this, but dexterous management of the 

 dipping tube will suffice to disperse all air-bubbles. — Thomas 

 CuRTEis, F.R.M.S. 



