A, M. Mayer—Remarks on Dr. R. Radau's paper. 201 
Exp. 4 et 5.—Je me suis éloigné du diapason no. 1 au lieu 
de m’en approcher. le résultat a été le méme que dans les 
exp. 2 et 3. 
Exp. 6.—J’ai fait vibrer, comme dans ee 1, le diapason 
ho. 8, qui faisait 254 vibrations par seconde. la balle ne 
bougea point. Alors jai détaché le diapason de sa caisse, et, 
me mettant & une distance de 80 pieds du diapason no. 1, j’ai 
balancé la caisse dans la main vers no. 1, mettant no. 3 dessus 
quand elle approchait no. 1 avee la vitesse couvenable (8—9 
Pieds par seconde). La balle fut subitement rejetée de no. 1. 
Sion ralentit ou accélére considérablement le mouvement de 
a 
XP. 
athe de plus que no. 1, fut substitué a celui employé dans 
Séloignait de no. 1. Le résu 
Peameements effectués dans la vitesse fut le méme que dans 
exp. 6. 
EXP. 8.—J’ai placé le diapason no. 8 devant la lanterne et 
balaneé le no. 1 comme dans aa 7, avec le méme résultat. 
Exp. 9,—J’ai placé le diapason no. 4 devant la lanterne 
Silanes Jono: commie: dann Vexp. 6. Le résultat fut le 
meme que dans l’exp. 6.” 
It is thus seen that K@nig’s method is founded on the pheno- 
mages of the fork arid cork-ball are Gale in greatly mag- 
tied proportions on a screen, they have been witnessed, with 
£ntire satisfaction, by an audience of nearly one thousand _per- 
“ons. In other words, Kénig’s are, we may say, subjective 
in their character, and the alteration of wave-length is interred 
™ the change in the frequency of the beats; while mine are 
*minently objective, and are directly intelligible from the visible 
mechanical actions produced by the forks. ay : 
It may be asked, why did I not mention Mr. Kénig’s beauti- 
ful experiments as a proper preface to my own? Before pub- 
lishing my results, [ examined into the literature of the sub- 
Ject as far as the journals and transactions of societies allowed, 
and I found nothing that interfered with my claim to the use 
of the forks, as well as the above application of the principle 
of the communication of vibrations, and the exhibition of the 
Same to a large audience by means of the lantern. It was only 
after my communication to the Paris Academy had been Yaa 
lished, ‘that my friend Professor Rood, of Columbia College, 
Owed me in Kénig’s catalogue the account of his experi- 
