350 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



It is added that " all that has been said applies equally to the 

 mounting of smuts, save that these being dark in colour do not need 

 to be stained, which is also true of many pollens." 



Brownell Turntable.* — Rev. J. T. Brownell has constructed a 

 turntable (fig. 89) upon the general plan of that devised some years 

 ago by C. M. Kinne, but with several important improvements. 



Fig. 89. 



Fig. 89, which is reduced to one-third of full size, represents the 

 table, front view. The stand A is made of wood, with the open 

 chambers A' A" A'", affording a convenient place for laying the 

 various utensils in use, and also for packing them together with 

 materials, &c., for transportation. The head-block B is of solid brass 

 4i X 1 in., and 1/4 in. thick. It stands on a spindle C 5 in. long, 

 which is supported by the metallic collars D and E. The lower end 

 of the spindle is dressed to a sharp point, and rests on a plate of 

 polished agate underneath the collar E. A couple of inches of the 

 central portion of the spindle are milled, and the instrument is run 

 by the tips of the fingers of the left hand placed against this milled 

 portion, while the hand is steadied by resting the thiimb against the 

 pillar F. The revolution of the slide is thus under the complete 

 control of the operator, who can readily keep it in uniform motion, 

 quick or slow, for any desired length of time. Fig. 90 shows the 

 upper side of the head-block, with a glass slip held in place. 



The clutches a (fig. 90) are set so as to gi-asp the slip diagonally, 

 bringing it to a true centre, and at the same time leaving one of its 

 comers projecting 3/8 in. on either side for convenient handling. 

 The clutches are secirred in position, being screwed fast to the brass 

 blocks X (fig. 91), which move firmly but freely through the grooves 

 cut for them. The lever-bars y are attached to these blocks by tho 



* Proc. Auier. fcjoc. Micr., 7th Auu. Meeting, 18Si, pp. 173-5 (3 figs.). 



