WORK TABLES 157 



In general a table provided with an indentation or cut-out 

 portion along one edge will be found to possess many advantages 

 over a simple straight-edge table. The worker, sitting well 

 up into the cut-out, secures support for his arms and is enabled 

 to sit up straighter; thus he is subject to far less fatigue during 

 long observations and manipulations. Moreover, in the greater 

 part of microchemical analyses or examinations more or less 

 corrosive vapors or gases are apt to be given off which it is desir- 

 able to keep as far away from the microscope as possible and yet 

 the instrument must be readily and immediately accessible with- 

 out material change of position. The indented table offers a 

 ready solution of this problem for if the microscope be placed to 

 one side of the indentation and the micro-burner and reagents on 

 the opposite side the worker has only to swing to the left or 

 right as the case may be to change his position from the most 

 convenient one for manipulations to that for microscopic obser- 

 vation. Fig. 90 shows the construction and arrangement of a 

 convenient work table for microchemical investigations. 



When an indented table is provided with drawers as shown in 

 the illustration, care must be taken in the construction to see 

 that the depth of those nearest the cut-out section is not so great 

 as to hit the knees of the worker as he swings from one side to 

 the other. 



The table top should be of close texture and finished in a dull 

 lusterless black. A polished or shining top should be avoided, 

 since reflections therefrom are always annoying and very tire- 

 some to the eyes. Glass, porcelain or stone tops should there- 

 fore be finished with dull or " ground " surfaces, never polished. 

 Coarse-grained woods should be avoided because of the dif- 

 ficulty of keeping them clean; for this reason the author prefers 

 table tops of whitewood or poplar, stained with aniline black, 

 unpolished and unvarnished, and merely rubbed down smooth. 



To guard against disfigurement and corrosion of the table top, 

 manipulations are performed upon a square piece of plate glass. 

 A convenient size will be found to be from twelve to eighteen 

 inches square. 



When possible the work table should be piped for gas and com- 



