6o 



PHYSIOLOGICAL RELATIONS 



done in a culture room (Fig. 14), and tin racks should be provided. 

 Miss Ferguson 1 has devised a convenient stand for holding slides 

 in cell culture work ; and since in many laboratories where infection 

 experiments are made, or where physiological work is done, large 

 numbers of these cells may be used, this stand becomes a very use- 

 ful device. It has been 

 described as follows : 



A stand for hanging-drop 

 cultures. A stand for support- 

 ing slides when one is using 

 the Van Tieghem cells should 

 be made of such material and 

 in such a way that it will 

 neither burn, warp, nor melt 

 upon being heated, for it is 

 often desirable to sterilize the 

 cells before making up the 

 cultures. It should also com- 

 bine economy of space with 

 ease of manipulation. All 

 these points are characteristic 

 of the little piece of apparatus 

 which I have used. . . . 



This stand consists, as will 

 be seen from the photographs 

 . . . , of a series of trays 

 placed one above the other. 

 Each tray was made from a 

 single piece of tin without the 

 use of solder. The tin meas- 

 ured 13 \ by 3! inches after it 

 was hemmed. This was folded 

 on the sides just as one folds 



a piece of paper in making the boxes described by Lee ( 1 896) for imbedding 

 material in paraffin. A strip i \ inches wide along both ends and on one side 

 was bent up at right angles to the rest, so that a box open at the top and along 

 one side was formed, which measured 1 1 by 2| inches on the bottom. The 

 double, triangular, carlike projections formed at the two corners were folded 

 along the back and secured by means of rivets. The tin was then cut, or 

 slashed. ;; of an inch deep, i inch distant from either corner on the back. 

 Similar cuts were also made at the corners, and three equally distant from 

 each other and from the- outer edges were made on either end. The segment 



FIG. 14. A SMALL CULTURE ROOM, CONVEN- 

 IENT AND EASILY CLEANED 



1 Ferguson, M. C, Bureau Plant Industry, Built. 16, /. 



