Root elevator Barry Fig. 12..
Root elevator Barry Fig. 17..
Root elevator Barry Fig. 18..
Root elevator Cryer Fig. 26..
Root elevator Seldin Fig. 27..
Root elevator Cryer Fig. 28..
Root elevator Cryer Fig. 29..
Root elevator Heidbrink Fig. 22..
Root elevator Heidbrink Fig. 23..
Root elevator Cryer Fig. 32..
Root elevator Kopp Fig. 31..
Root elevator Kopp Fig. 32..
Root elevator Kopp Fig. 33..
Root elevator Kopp Fig. 34..
Root elevator Kopp Fig. 35..