166 BOARD OF AGRICULTURE. [Jan. 



of beer, or as the least particle of yeast produces the sugar 

 transformation, or the least quantity of leaven turns a large 

 quantity of dough sour. 



" This power of transformation, possessed by a small quan- 

 tity of ferment, is one of the remarkable facts of science. It 

 is called by the celebrated chemist Berzelius, the ' Katalytic 

 power.' Figure III,, on a larger scale, may serve to explain 

 the milk pan Figure I., more fully. 



" In the bottom of the milk pan, near one end, is an opening, 

 «, through which the milk is drawn, after the cream is all 

 risen or separated from it, by raising a brass pin, b. The 

 opening is lined with brass, and is three-fourths of an inch in 

 diameter. A tin cylinder, c, is fitted into the opening, and 

 this is pierced, to the height of an inch, with many small holes, 

 diminishing in size towards the top. The cream is all risen in 

 twenty-four hours. I then draw the pin from the cylinder and 

 the milk flows out, leaving the thick cream, which is prevented 

 from flowing out by the smallness of the holes in the cylinder. 



" As the removal of all sour matter is of the utmost conse- 

 quence, the churn is also of great importance. Most churns 

 now in use are made of wood, and are apt to injure the butter 

 in consequence of their liability to infection with milk acidity. 

 To avoid this difficulty I have constructed a churn, as shown in 

 Figure IV., made entirely of tin, and I consider it better 

 adapted for its use than any now in use. The churn consists 

 of the following parts : — 



"a, a cylinder with two handles at the top, (the size of this 

 cylinder may be regulated by the quantity of cream to be used.) 



" Z), two flanges or projections from the outer edge of the 

 bottom of the churn, with holes through which it may be 

 screwed to the floor, so as to keep it steady while churning. 



" c, a kind of dasher, made of strong tin, and therefore 

 light. The lower part of the dasher is in the form of an 

 inverted tunnel, which fits pretty tightly to the inside of the 

 churn or cylinder. The tunnel is pierced with numerous holes. 

 This hastens the formation of the butter exceedingly, giving a 

 greater impulse to tlie dasher without great effort. The handle 

 of the dasher is so made as to be screwed on or taken ofi" at 

 pleasure. 



" d, the cover of the churn. It is of tin, and in the 



