2560 



Journal of Applied Microscopy 



the wall cases of the New York Museum is the use of green plush along the 

 bearing surfaces of the cases and doors. A method in use in Toronto, in the 

 mineral cabinet, is a tongue and groove (seen in Fig. 75), socketing into each 

 other tightly, the frame of the sash being held rigidly in place by screw bolts in 

 front and on the sides. The tongue is a triangular wooden cleet. Mr. Ferrier, 

 whose collection is thus installed at Toronto, claims that it enjoys complete 

 immunity from the invasion of dust in this way. The case is his own design. 



Fig. 74. — Ward-Coonley collection cases. 



A design, attributed to Prof. A. S. Bickmore, of a dustless case is shown in 

 Fig. 76, where a close box is made, opening only at one end, allowing a false 

 floor or body to be pulled out, a knee-leg supporting it when fully withdrawn. 

 The serious defect in this case was the impossibility of placing such cases near 

 together, and the very common vexation of finding the specimens disarranged 

 when the false floor was pushed back, as, owing to irregularities of surface, etc., 

 there were always jolts and hitches in its movement. 



Recently the use of glass alone in the construction of cases has reached, at 



