458 PROCEEDINGfl OF Tin: A M I : l ; U ■ \ N ACADEMY. 



mostly large forks, while tin- A forks were the ordinary musicians' small 

 A toning forks, toned by the authors to convenient pitches. The Bame 



forks were osed for several years subsequent to 1880. 



In the recent measurements three large standards of Coenig have been 

 used as a basis, viz.: a(', ol 266 doable vibrations, a tempered C« of 

 258.65 vibrations, and an A of 185 vibrations, at a Btandard temperature 

 of 20 C. Prom these were rated l>y the method of beats, a series of 

 rks and also two Bets of (', Bmall Scheibler's tonometer forks 

 by Koeuig, and two sets of A 3 forks of the same character. These Bmall 

 tonometer forks were also compared with a series of large Scbeibler 

 tonometer forks by koeuig, which last were assumed to be Correct within 

 the limits Bought in our measurements. 



Table II. gives the results of ratings of various standards of epochs 

 indicated by the date. In all measurements later than 1891 the rloenig 

 Btandard tonometer forks have been employed. The data given in 

 Table II. are all in terms of the pitches of (', and A .... The pitch of the 

 Btandards actually measured is specifically stated in all cases except when 

 it is (', or A 3 . 



Table III. contains the results of measurements of fifty-^i x forks 

 by various manufacturers to the Committee of the National Piano and 

 Organ Manufacturers' Association in response to their request already 

 referred to. A preliminary rating was made by me in 1890—91 with 

 such forks as I then possessed. The results of this were shown m a 

 circular privately printed in 1891 for the use of memhers of the Associa- 

 tion. A more exact determination was made by me a few month- later 

 in 1891, using the Koeuig tonometer forks as previously stated. The 

 results of these measurements are found in the table. 



Certain of the forks and other standards referred to in Table II. 

 deserve special mention. Those numbered 4, 5, G, 7, 9, 10, 11. 12, 1.'!, 

 1 1. 1"'. 16, 17, 18, 19, 87, 88 were intended to give the physical pitch. 

 Nos - and '■'< had been in the possession of their owners for many years, 

 and wen- authenticated as to the date assigned to them. No-. 5 ami G 

 arc two forks belonging to Harvard University, imported many years 

 since. No. 5 is of the early Marloye pattern, with inclined prongs, hut 

 does not hear any mark to indicate the maker. No. 6 bears the mark 

 M R. K," always employed by Koeuig. Nos. 1G and 17 are also Koenig 

 forks of early date, belonging to Harvard University. No. 8 is a pitch 

 pipe formerly employed for church use, belonging to Mr. 1J. .J. Lang of 

 Boston. It is a whistle with a movable plug, and the pitch can be varied 

 through an octave. When the plug is set for C 4 , according to the lines 



