8 WALLACE CLEMENT WARE SABINE— HALL [MEM0IES [voL.xxi r ; 



2.31 seconds with the same tone. The practical results satisfied the director, Mr. Gericke, at 

 once and have now been approved by the audiences of many years. 



It is interesting to note, in passing, that Messrs. Wheelwright and Haven, architects in 

 1902 of a new building for the New England Conservatory of Music, called on Sabine for help in 

 regard to the acoustics of moderate-sized rooms intended for piano practice. Seeing that he had 

 to do here with a question of musical taste, not one of physics merely, he experimented with 

 five different rooms, varying the furnishings in each till a jury of musicians declared themselves 

 satisfied. Then, measuring the duration of reverberation of C 4 in each of the rooms, as approved, 

 he found the shortest time to be 0.95 second and the longest 1.16 seconds, the mean being 1.08 

 seconds, less than one-half the approved time for a symphony concert hall. 



Sabine tells us (p. 199 of his Collected Papers) that investigation of the absorption coeffi- 

 cients of different materials for the single note of violin C, the " C 4 " mentioned above, "required 

 every other night from twelve until five for a period of three years," yet this study, vastly 

 important as it had proved to be, was not enough: 



It can be shown readily that the various materials of which the walls of a room are constructed and the 

 materials with which it is filled do not have the same absorbing power for all sounds regardless of pitch. Under 

 such circumstances the previously published work with C« 512 must be regarded as an illustration, as a part 

 of a much larger problem — the most interesting part, it is true, because near the middle of the scale, but, 

 after all, only a part. Thus a room may have great reverberation for sounds of low pitch and very little for sounds 

 of high pitch, or exactly the reverse; or a room may have comparatively great reverberation for sounds both of 

 high and of low pitch and very little for sounds near the middle of the scale. In other words, it is not putting it 

 too strongly to say that a room may have very different quality in different registers, as different as does a musi- 

 cal instrument; or, if the room is to be used for speaking purposes, it may have different degrees of excellence or 

 defect for a whisper and for the full rounded tones of the voice, different for a woman's voice and for a man's — 

 facts more or less well recognized. Not to leave this as a vague generalization, the following cases may be 

 cited. Recently, in discussing the acoustics of the proposed cathedral of southern California in Los Angeles with 

 Mr. Maginnis, its architect, and the writer, Bishop Conaty touched on this point very clearly. After discuss- 

 ing the general subject with more than the usual insight and experience, possibly in part because Catholic 

 churches and cathedrals have very great reverberation, he added that he found it difficult to avoid pitching his 

 voice to that note which the auditorium most prolongs notwithstanding the fact that he found this the worst 

 pitch on which to speak. This brings out, perhaps more impressively because from practical experience instead 

 of from theoretical considerations, the two truths that auditoriums have very different reverberation for different 

 pitches, and that excessive reverberation is a great hindrance to clearness of enunciation. Another incident may 

 also serve, that of a church near Boston, in regard to which the writer has just been consulted. The present 

 pastor, in describing the nature of its acoustical defects, stated that different speakers had different degrees of 

 difficulty in making themselves heard; that he had no difficulty, having a rather high pitched voice; but that the 

 candidate before him, with a louder but much lower voice, failed of the appointment because unable to make 

 himself heard. 



Accordingly, about 1900, Sabine undertook an extension of his investigations to cover 

 nearly " the whole range in pitch of the speaking voice and of the musical scale," from C„ of 64 

 vibrations per second, to C 7 , of 4,096 vibrations. Carrying meanwhile his full share of work as a 

 conscientious teacher and seizing time and opportunity as best he could for research, he 

 was engaged about five years with this new labor. 



The difficulties and devices of the undertaking can best be shown by certain quotations : 



In the very nature of the problem, the most important datum is the absorption coefficient of an audience, 

 and the determination of this was the first task undertaken. By means of a lecture on one of the recent develop- 

 ments of physics, wireless telegraphy, an audience was thus drawn together and at the end of the lecture requested 

 to remain for the experiment. In this attempt the effort was made to determine the coefficients for the five 

 octaves from C2 128 to Ce 2048, including notes E and G in each octave. For several reasons the experiment was 

 not a success. A threatening thunderstorm made the audience a small one, and the sultriness of the atmosphere 

 made open windows necessary, while the attempt to cover so many notes, thirteen in all, prolonged the experiment 

 beyond the endurance of the audience. While this experiment failed, another the following summer was more 

 successful. In the year that had elapsed the necessity of carrying the investigation further than the limita 

 intended became evident, and now the experiment was carried from Ci 64 to C7 4096, but included only the C notes, 



9 It is not surprising that in 1899 Sabine had an attack of appendicitis that very nearly proved fatal. With his strange, fanatical disregard for 

 pain, he had ignored all warning symptoms, had kept on his feet, and was out of doors, on Cambridge Common I believe, when the abscess broke. 

 As soon as he was out of immediate danger he laughed at this adventure and announced his intention of making a record recovery, which he did. 

 He was two weeks in the hospital, one week at home, and then began the work of the opening college year, " blithely and smilingly with springing 

 stop," to use his mother's words. 



