12S 



M \CHINT. ii;\\vis<; \\i ii 



KXEi />..,, r/,,1.-/.-. --In li-4. l-J'J tin- riiiht lian-l 



:" the ilhi8tr.it i.. n shuwM ;i half fmnt . : .11. 1 a half 



back elevation of the chuck. The UI.J..T half of h.-iml 



lM,rti..n shows a section by a jilaiH- <-"]Hainin- ih the lah-- 



the axis of one of the jaw-screws, \\liilr tin- l..\\n half 



Flo. 122. 



Fio. 123. 



