116 KANSAS UNIVERSITY QUARTERLY. 
acid may be readily detected by zinc and HCl, as about 1 c.c. of 
a 2.2000 solution of calcium sulfite in cider when treated with a few 
scraps of zinc and about six c.c. of concentrated HCl, promptly 
gave the unmistakable odor of hydrogen sulfid and darkened lead 
acetate paper in less than one minute. 
Neither HCl nor H,SO, in 1-4000 and 1-2000 solutions in cider 
gave evidence of SO,, but 1-1000, 1-500 and 1-250 solutions gave a 
somewhat pungent odor; none of them, however, produced a color 
with mercurous nitrate paper (paper saturated with mercurous ni 
trate solution). Potassium bichromate was not sensibly reduced by 
the amounts present in the above solutions, but the 1-250 solution 
gave an olive green color, not characteristic. Sodium nitroprus- 
side gave no results whatever. 
Quantitative determinations were not attempted, but for those 
interested reference might be made to the method in use by the 
Union of Baverian Chemists, described in U. S. Bull. 13, page 3. 
It consists in acidulating with phosphoric acid, distilling in a cur- 
rent of CO, then collecting in a solution of iodine. The sulfuric 
acid formed is then estimated in the usual way as barium sulfate. 
Table 2 shows the effect of various amounts of calcium sulfite 
upon cider treated in the same manner as those previously men- 
tioned. One more distillation was made of each sample and titra- 
tions were calculated as acetic acid as before, although in all 
probability the acidity in Nos. 1, 2, 3, and 4, was wholly due to 
the malic acid of the fruit. 
TABLE: 2. 
PER CENT OF 
PER CENT OF ALCOHOL. Te a ee 
Interval. Ba" (24 h./72 lal otal [22 d. 152 d. ea qd) BiiGha | oh Qe 
Strength. | | 
DG hy B25 0s «+h OF. OrF | OB] OG.) Guy 0.57 0.41 
Oye e RG DO OMe | Oe. \nOr Savors le Bnd 0.48 0.41 
Mer sre rObO 10,51 O19" | 6.8 | eyo) |p 34) | 0.41 0.41 
IN OW) ApoE EROOO HN Ons" Ova | 0.9 | Heo) 4) One 0.41 0.41 
INOe): Si eOOON sia Ov Sor Or. 0.9) eln5ie | FeO. sy One 0.41 ane) 
No. 6, blank obtuse ne Pet ae Re 1.62 3.48 
Here the effect of the increasing quantity of the preservative is 
very plainly shown, and evena ;,'5, solution has a noticeable effect. 
The action of the sulfite seems to be retarding only, for consider- 
able alcohol is produced after the fifty-second day, even in a »#y 
solution. The formation of acetic acid is much retarded. 
