24,327. Prager, M. Oct. 24. Reciprocating stirrers; containers; discharging-appliances.-In the manufacture of acetic acid, a mixture of calcium acetate and sulphuric acid or bisulphate is passed with continuous agitation through a series of heated chambers arranged one behind another. In the apparatus shown in Fig. 1, the acetate is fed through a hopper into a chamber c<1> and sulphuric acid is supplied from a perforated oscillating spindle e. Mixing is effected by a blade arranged on the oscillating spindle, and the mass is gradually passed from one chamber to the next by means of scoops arranged on the spindle opposite to the mixing-arms. On the plate i the mass is further mixed by rotating blades, and then, by means of scraping-blades, passed into chambers c<4>, c<5>, &c., in succession, where it is further mixed as in c<1>. The residue is discharged at u.