Chloride and Oxygen Analysis Kit — Dean and Hawley 
111 
ther in Dean and Fetcher (1942: 237; see 
also Dean: unpublished). For the oxygen 
determination a solution of thiosulfate is 
used in the burette and a 2-inch 2 2-gage 
hypodermic needle bent downward at 90° 
serves as the delivery tip. The chloride de¬ 
termination requires a strong solution of 
silver nitrate, which corrodes all available 
metals, so that a glass tip must be used. In 
this apparatus we used a bent glass tube 
attached to the burette by a number 0 one- 
hole rubber stopper. 3 
3 The Ace Glass Company, Vineland, N. J., is 
now able to supply ground glass tips to order 
which will fit on a standard hypodermic syringe. 
The titration vessel is a shortened test tube 
about 25 mm. in diameter and 70 mm. long. 
It fits in a wire test tube holder which is 
attached to the electrode jack assembly. The 
burette tip and the two electrodes dip into 
the solution in the titration vessel. In addi¬ 
tion there is a glass tube to introduce air 
bubbles for stirring. Air is forced by an 
aspirator bulb into a 1-liter can which 
serves as an air reservoir, and flows from 
there through a thin rubber tube to the glass 
nozzle of the air stirrer. The aspirator bulb 
can be conveniently squeezed by the left 
hand of the operator during a titration. 
A reagent shelf over the air reservoir 
H lo.ooo | — 
12.00 
MICRO AMPS 
1 -I 10,000 1-1 
P^standardA 
S2 
V^/ CELL 
DETAIL OF 
ELECTRODES 
Bronze 
wire in 
glass 
Radio 
jack 
|Pt or Ag 
wire 
Fig. 2. Wiring diagram. Si and S 2 are two parts of a double-pole, double-throw telephone-type 
toggle switch. Wires run from the Pt, Ag, and Cu terminals to the electrode holder. 
