25U8 



Journal of Applied Microscopy 



The bayonet and short bracket are perhaps more pleasing in appearance, are 

 not so obvious, but are only safely used for less heavy objects. With glass 

 shelves the short bracket produces excellent results, and for pottery, glass, small 

 figurines, etc., seems admirable. For greater strains the bayonet bracket can be 

 reinforced by thickened and deepened keel (see Fig. 55). 



The use of glass shelves in high cases has received a great deal of endorse- 

 ment, and certainly for many types of exhibits can be favorably regarded. Glass 

 shelves, as being unpainted, remain permanent in appearance, and can be cleaned 

 far more perfectly and easily than wood ; they are quite strong, and their elusive- 

 ness and transparency to the eye gives the interior of cases a more agreeable 

 expression than wood, in many instances. On the other hand, wood is strong, 

 and for minerals, fossils, economic exhibits, building stones, etc., even for some 

 zoological exhibits, is to be preferred, while wood, as being adapted to the use of 

 colors, can be conveniently used as a background for the heightening of effects. 



Fig. 51 



-Wall cases covering angle between walls. Crane 

 Museum, Pittsfield. 



And of course, in the exigences of museum installation, when shelves must be 

 sawn in two, or apertures and openings made through, to accommodate high or 

 irregular specimens, wood has a plasticity quite irreconcileable with the use of 

 glass. Iron shelves painted or covered with leather can hardly be recommended. 

 They are incombustible, but they are very heavy and clumsy, and offer but few 

 advantages. 



The interior walls of high cases can be made of wood or lined with zinc, to 

 insure dryness, or a board used covered with a linoleum cloth. This latter 

 device furnishes an attractively grained background, is not subject to the warp- 

 ing and folding of metal plates, and is not impervious to tacks, nails and other 

 fixtures. 



A word may be profitably added upon the inexpediency of putting wall cases 

 past the angles or corners of halls. A wall case built upon two walls and cover- 

 ing also the angle between them (speaking only of rectangular halls) while in a 



