W. B. Taylor— Becent Researches in Sound. 31 



plastered surface of 64 square feet, produced a sensible increase 

 of effect in the sound, within a distance of 500 yards in front 

 of the signal : beyond this distance, the difference became im- 

 perceptible. It appeared that " while feeble sounds at small 

 distances are reflected as rays of light are, waves of powerful 

 sound spread laterally, and ev( 

 mouth of a trumpet, at a great 

 whole circle of the horizon." (L. H. Eep., p. 88.) A trumpet, 

 however, which could be heard six tniles in front (in the direc- 

 tion of the axis) was heard only three miles in the rear. (p. 92.) 

 [2.] " For determining the relative power of the instruments, 

 the use of two vessels had been obtained." The instruments 

 at the light-house station were a large bell, a steam-whistle 6 

 inches in diameter, a double whistle, " improperly called a 

 steam gong," 12 inches in diameter, the cups being 20 and 14 



inches deep, producing the harmonic interval of i 

 h, and a Dat " ' 



)aboll t 



■ engine was also 

 noted. " The penetrating power of the trumpet was nearly 

 double that of the whistle." (Eep., p. 90.) The order of au- 

 dible range on the first day was found to be 1st, trumpet, 2nd, 

 exhaust, 3rd, bell, the whistle not being sounded. On the sec- 

 ond day, 1st, trumpet and "gong," 2nd, whistle, 3rd, exhaust. 

 In the rear the trumpet was heard no farther than the whistle. 

 On the third day, the order was similar, — 1st, trumpet, 2nd, 

 whistle, 3rd, exhaust, 4th, bell. (p. 91.) The opportunity was 

 unfavorable to the observation of these sounds when they were 

 moving directly with the wind. 



[3.] Simultaneous observations from two vessels sailing in 

 nearly opposite directions, showed that the sound did not ex- 

 tend against the wind so lar as in the direction of the wind ; 

 and on subsequent days, results obtained from sounds moving 

 nearly against the wind, and at right-angles to it, indicated that 

 an opposing wind, when light, obstructed sound less than when 

 stronger, and that wind at right-angles to the sound, permitted 

 it to be heard farther. (Eep., p. 92.) 



[4.] '^During this series of investigations an interesting fact 

 was discovered, namely, a sound moving against the wind, in- 

 audible to the ear on the deck of the schooner, was heard by 

 ascending to the mast-head." (p. 92.) These results were ob- 

 tained in 1865. 



[5.] An experiment subsequently made at Washington during 

 a fog, with a small clock-work alarm bell, indicated that the 

 fog did not absorb sound ; though want of the opportunity of 

 a comparative observation prevented the result from being en- 

 tirely satisfactory, (p. 93.) 



In 1867, the principal object of investigation was a compari- 



