Thus so that z 1 J1 2 (z) = - 2 Jo 2 (z) - qz.h2(Z), (' an n z 1 J i 2 (z)dz = 1 -Jo (z) - J 1 2 (z).
We have also the geometrical relations x = (a/c) (qz ry), 5 = (a/c) (rx p1), = (a/c) (pyqx).
The Samanids (qz.) were the first really important nonArabic Persian dynasty since the fall of Yazdegerd III.
It is evident that the discharged heat Qz is equal to the abstracted heat Q ', plus the work expended, seeing that the work W, which causes the rise in temperature from T 1 to Tz, is the thermal equivalent of the energy actually expended in raising the temperature to the level at which it is rejected.