32 On the Construction of Buildings, etc. 
the cushioned seats on the floor of the hall afforded sufficient ma- 
terial for the absorption of sound. And it is an easy matter to 
increase this effect to any required extent, by the judicious em- 
ployment of upholstery and carpeting. 
GALLERIEs are generally regarded as prejudicial to sound. But 
they are almost necessary evils, when it is required to accomodate 
with comfort an auditory of three or four thousand persons, with- 
out extending unduly the area of the floor. What adds much 
to their injurious effect is the unreasonable depth with which 
they are ordinarily constructed, thus necessitating for their sup- 
port the use of pillars, by which the pulses of sound are inter- 
rupted and broken: and when, as is mostly the case, these gal- 
leries have floors shelving back to the wall, with no provision for 
ventilation at that point, they become (as we have before sug- 
gested) vast receptacles for the impure air beneath. It seems to 
us, moreover, that a gallery, although it be so fashioned as to 
escape the evils just mentioned, is injurious in other respects, to 
the musical qualities of a room, when placed in immediate con- 
tact with its walls; for by impeding the free vibration of the 
latter, it must tend to destroy their resonance, acting, in this case, 
much in the same way as a damper placed upon a vibrating string, 
or a mute on the bridge of a violin. 
The position of the orncHEsTRaL stace has become fixed by 
custom. ‘There are those, however, who would have it removed 
to a point nearer the centre of the room, and for good philo- 
sophical reasons. Chladni and Herschell are among the advo- 
cates of this change, on the ground that the original impulse, 
being then more equally distant from all the walls, the hearer 
would suffer less from the effect of secondary or reflected sounds. 
On the same principle it might be urged also that the platform 
should be raised much higher from the floor than is usual, in 
order to lessen the appreciable amount of reflection from the roof- 
Considered wholly in reference to the truthful interpretation of 
the sound by the room itself, such is no doubt the correct doc- 
trine. But in the first instance, we should lose the benefit of 
a solid reflecting surface behind, which serves to reinforce the 
original sound by a reflection so nearly synchronous with it as 
not to be appreciable by the ear; and in both , aconsiderable por- 
tion of the assembly must be deprived of a favorable view of the 
occupants of the stage. It is better, perhaps, to adopt a middle 
course between the two in this respect, aiming to satisfy, as nearly 
as may be, the acoustic requirements of the room with a just 
regard to the comfort and convenience of the audience. 
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