TABLE 109. 



VELOCITY OF SOUND IN AIR. 



Rowland has discussed (Proc. Am. Acad. vol. 15, p. 144) the principal determination of the velocity of sound in 

 atmospheric air. The following table, together with the footnotes and references, are quoted from his paper. 

 Some later determinations will be found in Table in, on the velocity of sound in gases. 



General mean deduced by Rowland, 331.75. 



Correcting for the normal carbonic acid in the atmosphere, this becomes 331.78 metres 

 per second in pure dry air at o C. 



REFERENCES. 



1 French Academy : " Mem. de 1'Acad. des Sci." 1738, p. 128. 



2 Benzenburg : Gibberts's " Annalen," vol. 42, p. i. 



3 Goldingham : " Phil. Trans." 1823, p. 96. 



4 Bureau of Longitude : " Ann. de Chim." 1822, vol. 20, p. 210 ; also, " CEuvres d'Arago," 



" Mem. Sci." ii. i. 



5 Stampfer und Von Myrbach : " Pogg. Ann." vol. 5, p. 496. 



6 Moll and Van Beek : " Phil. Trans." 1824, p. 424. 



7 Parry and Foster : " Journal of the Third Voyage," 1824-5, Ap 



1828, p. 97. 



8 Savant: " Ann. de Chim." ser. 2, vol. 71, p. 20. Recalculated. 



9 Bravais and Martins : " Ann. de Chim." ser. 3, vol. 13, p. 5. 

 10 Regnault: " Rel. des Exp." iii. p. 533. 



p. 86 ; " Phil. Trans." 



a I believe that I calculated these reduced numbers on the supposition that the air was rather more than 

 half saturated with moisture. 



b Reduced to o C. by empirical formula, 



c Wind calm. 



d Moll and Van Beek found 332.049 at o C. for dry air. They used the coefficient .00375 to reduce. I 

 take the numbers as recalculated by Schroder van der Kolk. 



* An error of 0.21 C. was made in the original. See Schroder van der Kolk, " Phil. Mag." 1865. 



f Corrected for wind by Galbraith. 



g Recalculated from Savart's results. 



* This is given as 1864 in Rowland's table. The original paper is in " Me'm. de 1'Institut," vol. 37, 1868. 



SMITHSONIAN TABLES. 



99 



