J. LeConte on Binocular Vision. 169 
5] 14; 
sight, 
B’ will be . 
. If, now, while B | 
the sight is still fixed 
upon A, B be elevated, A 
it 
ing to Meissner, will ap- | 
dee d, ma. Pp 3 é Me: 
line WAO is, therefore, the Horopter or line of single vision. 
It is not at right angles but inclined to Pe plane of vision, 
\gain, according to Meissner, if instead of po ve ver- 
tical Yines like threads WB and OB’ (fig. 11), then OB’ will 
* i Ye: Aschiv. dea foe L. iii, p. 138 and 225. eee 
at hog oe 1864. = * Bib. Ua. Arch. des Scien., vol. iii, p. 138. 
AM. Jour, Scr.—Sgconp SERIES, VOL. XLVII, No. 140.—Mancu., 1869. y 
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