CASEIN : ITS OKIGIN, PREPARATION AND PROPERTIES. 13 



the main shaft passing through it. On the other hand, the 

 machines take up less room than those driven from under- 

 neath. A typical centrifugal machine with bottom driving 

 is that of Haubold (Chemnitz), shown in Fig. 5, for which 

 the maker claims the following points of superiority : (1) 

 Perfectly even and noiseless running, combined with low 

 cost of up-keep; (2) absence of any masonry foundation, 

 which is replaced by a strong wooden frame, enabling the 

 machine to be set up in any convenient place, even in upper 



FIG. 5. Section of Haubold's Patent Centrifugal Machine with 

 Bottom Discharge. 



storeys; (3) small consumption of motive power, drum per- 

 fectly clear inside ; (4) driving mechanism situated under 

 the drum, preventing any contamination of the contents by 

 dropping oil ; (5) careful and solid construction of the various 

 parts, with minimum wear and tear ; (6) high speed combined 

 with perfect safety. 



The drums are constructed and arranged in such a man- 

 ner that the contents are expelled with perfect regularity. 

 They are usually made of sheet copper, though for special pur- 

 poses use is made of steel, wrought or cast iron, aluminium, 



