with Reference to Sound. 23 
gencity which it is our aim to preserve. It is analogous in its 
effects to the sheathing of a musical instrument. 
One other question of practical utility comes up in this connec- 
tion, viz.: as to the comparative superiority of thus battening and 
wainscoting such solid wall with wood, or of lathing and plaster- 
ing it in the usual manner. Our preferences are in favor of the 
employment of wood for this purpose, substantially for reasons 
above stated. 
As regards the subjects of venriLaTinc, WARMING and LIGHTING, 
they have a broad range, and demand alike the attention of the 
architect, the philosopher and the philanthropist. Hitherto their 
importance, even in a sanatory point of view, has been too often 
overlooked or neglected. But aside from a due consideration for 
the health and comfort of a crowded audience, they are points 
which affect materially the acoustic properties of a room. 
The conditions of the external atmosphere required for the 
greatest intensity, clearness and purity of tone, have been fully 
stated in a previous number. The effect of the different gases, 
and of a mixture of gases, vapors, or liquids of different chemical 
and mechanical natures, upon the communication of sound, has 
likewise been shown. From such facts and illustrations it is 
plain that whatever conduces to the purity of the contained air 
oF a room, to its quiescent and equable state, uniformity of tem- 
perature and freedom from draughts and partial currents, adds to 
the truthful interpretation of sound therein. We are convinced 
the matter has not yet been sufficiently considered in this light, 
although the attention of the public has at various times been di- 
rected this way*. Dr. Bell, in his instructive address delivered 
before the Massachusetts Medical Society, in May, 1848, on the 
Practical Methods of Ventilating Buildings, thus recognizes the 
claims of his subject in this particular. 
6s 
ls more palpable and material admixtures. At first thought, it may 
®ppear somewhat fastidious, and even unphilosophical, to regard merely 
unwelcome sounds, recognized by the ear alone, in the light of offen- 
Sive impurities, or rather as disagreeable additions to the medium in 
which we live and intercommunicate, yet no explanation will be needed 
by a body of medical practitioners, residing, in part, in arge tow 
and. ciliés, for considering the means of obviating, or ae 
* * *% * x % * : 
“Ttisa gratifying coincidence, which will most fully develop itself, 
8s the various modifications of the ventilating system are brought for- 
* Vide Reports of the Parliamentary Committee in 1833 and 1836; and the able 
treatises on ventilation and warming by Tredgold, Reid and Wyman. 
