2458 



Journal of Applied Microscopy 



walls where the requirements of construction are such as to forbid windows or 

 skylights are of course impossible. Recourse must then be had to pier wall 

 cases extending well out into the hall, or the use of the wall along such expos- 

 ures as are insufficiently lighted must be minimized, or every device adopted 

 for getting the best diffused illumination possible. A very obvious remedy, 

 where on one side of a hall a long wall space is available and which cannot be 

 pierced with windows, while the opposite wall may form the front of the build- 

 ing, is to open the latter with high or broad windows, so as to flood the closed 

 wall with light, while at the same time abundant diffused light is secured for 

 lighting the central exhibits of the hall. In such a case the central exhibits 

 should be in flat table cases in order that the least obstruction should be offered 

 to the incident light. 



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Fig. 42. — Typical Wall Case with dimensions. 



The practice of using glass tops to cases, as recommended by Dr. Goode, 

 seems questionable, except in group cases where the appearance of the case 

 itself is improved. Dust soon accumulates on the glass or it becomes otherwise 

 dirty, and it requires frequent cleaning, while when objects are raised above the 

 cases the glass is an obstruction and danger to their manipulation. Dimensions 

 of wall cases of course vary, their depth being dependent on the character and 

 size of the objects they are intended to hold. A depth of three feet seems 

 widely serviceable. 



The doors of all upright cases should be swing doors, opening outward for 

 the one sufficient reason that they can be easily cleaned. Dr. Goode's advocacy 

 of doors pushing upward (Fig. 41) was induced by supposed value of the broad 

 glass pane such an adjustment allows, which of course may have advantages. 

 But in practice it will soon be found that the lid which is pushed open by the 

 ascending sash and which falls again upon the latter's descent cannot be kept 

 dust proof, and that every time it is opened it dispenses some of its accumula- 

 tions upon the objects and shelves in the interior of the case. It is altogether 



