1309 
3 C (es Hoe, Hed LiH De, Hes Fe) LE + | 
+ DIe, (e, He) Hes (1 + es) 4 ADE F6) | 
E [e,'e,'¢, + €, 0,6, En, — Ee, 2e, — €, Ca] 
4 1 
(9) 
These parts should be added to A/,'* + ap therefore the co- 
efficient of e',? increases by 
3C (e, + ey + es) En D (e, +f A 
that of e,e€', by 
(6C + 2D)(e, He, + ¢) + (D+ Be 
that of e',? by 
—1Dé€, He, + ¢,)— Ee, 
from which the other follow by cyclic change. In order to introduce 
the notation of Vorer also for the isotropic body one should remember 
that c¢,,=¢,,—C,,, whereas A=1c,,, B= — 2c,,. From this 
therefore the constants for the rhombic erystal are at once to be 
written down. From the elastic differential equation afterwards the 
determinant equation for the velocity of transmission in its depen- 
dence upon the direction is deduced, and also the frequency of the 
normal vibrations can be determined. The further, more detailed 
calculation will finally for the mean values in question, except the 
terms which appear also in the isotropic case, yield values which 
linearly depend on ¢,, e, and @;. 
3. In a note to our contribution (1) already we have pointed 
to the fact that the ordinary formula which was used there for the 
tension was not exact. In the following manner the accurate form 
for finite deformations is found. 
The elastic energy e can also in that case be represented by the 
already often used formula (I), provided only that the correct 
signification is assigned to the quantities e,...e,. Liet us now represent 
the differential quotients oe ae ete. by a,,, dj, ete., then we must 
Oz Oy 
take ') 
e=, + $(a1’ + 4, fart a a (11) 
e, = Ass + Asa + Aran Hr Analog T Agalaa: 
From the energy « it will be possible to find the tension A, by 
means of a virtual elongation d in the z-direction. This now has to 
be composed with the known deformation, which is determined by 
the magnitudes a,, ete. Hence a,,, a,, and a,, change and further 
also all magnitudes e. For the new values we find 
1) Vide e.g. LOVE. 
