82 PROCEEDINGS OF THE AMERICAN ACADEMY. 



cover all the ground that should be covered. It is highly desirable 

 that data should be accessible for glass surfaces, for glazed tile surfaces, 

 for plastered and unplastered porous tile, for plaster on wood lath and 

 plaster on wire lath, for rugs and carpets ; but even with these data 

 collected the job would be by no means completed. What is wanted 

 is not merely the measurement of existing material and wall surfaces, 

 but an investigation of all the possibilities. A concrete case will 

 perhaps illustrate this. If the wall surface is to be of wood, there 

 enter the questions as to what would be the effect of varying the 

 material, — how ash differs from oak, and oak from walnut or pine or 

 whitewood ; what is the effect of variations in thickness ; what the 

 effect of panelling ; what is the effect of the spacing of the furring on 

 which the wood sheathing is fastened. If the wall is to be plaster on 

 lath, there arises the question as to the difference between wood lath 

 and wire lath, between the mortar that was formerly used and the 

 wall of to-day, which is made of hard and impervious plaster. What 

 is the effect of variations in thickness of the plaster 1 What is the 

 effect of painting the plaster in oil or in water colors ? What is 

 the effect of the depth of the air space behind the plaster ? The 

 recent efforts at fireproof construction have resulted in the use of 

 harder and harder wall surfaces, and great reverberation in the room, 

 and in many cases in poorer acoustics. Is it possible to devise a 

 material which shall satisfy the conditions as to fireproof qualities and 

 yet retain the excellence of some of the older but not fireproof rooms 1 

 Or, if one turns to the interior furnishings, what type of chair is best, 

 what form of cushions, or what form of upholstery 1 There are many 

 forms of auditorium chairs and settees, and all these should be in- 

 vestigated if one proposes to apply exact calculation to the problem. 

 These are some of the questions that have arisen. A little data have 

 been obtained looking toward the answer to some of them. The diffi- 

 culty in the way of the prosecution of such work is greater, however, 

 than appears at first sight, the particular difficulties being of opportunity 

 and of expense. It is difficult, for example, to find rooms whose walls 

 are in large measure of glass, especially when one bears in mind that 

 the room must be empty, that its other wall surfaces must be of a 

 substance fully investigated, and that it must be in a location admit- 

 ting of quiet work. Or, to investigate the effect of the different kinds 

 of plaster and of the different methods of plastering, it is necessary 

 to have a room, preferably an underground room, which can be lined 

 and relined. The constant temperature room which is now available 

 for the experiments is not a room suitable to that particular investiga- 

 tion, and for best results a special room should be constructed. More- 



