G88 CATTLE AND DAIRY FARMING. 



prevent evaporation. The. position of the scale is then rend off, that part being read off 

 which coincides with the middle part of the deepest curved line on the surface of the 

 liquid. The temperature during the estimation of.the.specilic gravity of the solution 

 must be noticed, and if it is IT . 5 C. the specific, gravity will need no farther correc- 

 tion, fur it in* I-' t be understood that it is diminished by a higher and increased by u 

 lower temperature. The temperature of the water in A may fluctuate from 16. 5 to 

 l^-\5 C., and the s-pecitie gravity of the ethereal solution at 17 D .f> C. having been found, 

 The amount of fat in weight per cent, can be obtained from the table supplied with the 

 instrument. The value of the .Soxhlet apparatus is that the percentage of fat to the 

 second decimal place is obtained, thus making it as valuable ad actual analysis. 



CREAM-SEPAKATIITG MACHINES. 



REPORT PREPARED F32 CONSUL SHAW, OF MANCHESTER, EY J/R. JAXL1S LOXG, OF 



JIETC1I1X, ENGLAND. 



Up to the present time the most popular machine in England and France has been 

 the Dz Laval, which is the only one that has been regularly exhibited. There are two 

 reasons for its popularity its price, which has varied between oO and 37, and its 

 value for it is a good machine. Perhaps it also ought to bo said that it lias no opposi- 

 tion in either country, for this is almost the Jhct. True, three other machines have 

 been exhibited in England; but in one case, the " Danish," patent difiiculties have pre- 

 vented its sale: in another, the ''Lefeldt," is very much more expensive; and in the 

 third, the "J'ctersen, " a quite new machine, which competed at the Royal last year 

 against the Laval for a gold medal. It was far higher in price, suitable only for big 

 dairies and factories, and did not take off all the cream. There is, however, a difficulty 

 with the Laval, which its inventor can not overcome: it requires a great deal of power 

 for so small a machine, and it cannot be made in smaller or larger sizes, these .being 

 most insuperable objections when, rival machines are introduced without them. 



The De Laval is the invention of a Swede of that r.ame, but it is not the earliest in- 

 vention, for centrifugal force, which is in reality forced gravitation, as applied by an 

 English inventor, was first used by a German, Professor Fuch, as early as 18.19. In 

 Laval's machine the receiver revolves with the milk :--omo o,()0() times a minute and 

 takes the cream from some, 'J(li) quarts an hour. This receiver, which is made of steel, 

 works upon a vertical axis, and is filled with the milk through the medium of a funnel 

 wh : ch passes into it from above. As the milk revolves, the centrifugal action causes 

 tij". lighter cream to gather at the top in the center, while the heaver portion of tho 

 volume is forced to tho outside. This being the case it only needs some additional out- 

 side power to force it outside and this is provided by the continual stream of new milk. 

 The p-sult is that the heavy skim, milk is compelled to lind its way through a tube to 

 an outer chamber whence it runs out by a pipe. As the new milk enters and is skimmed 

 the enJiij-L'ed volume of cream likewise demands an outlet, for -it cannot get to the per- 



hery nor escape with the milk; hence it is provided with a special tube and chamber, 

 nd <.- capes from another portion of the machine in a similar way. As the drum is 

 J 1 nn ler.-i in diameter, the surface speed of the interior required to separate the cream 

 i.> all ut l.~>,0i)(i feet ^er minute. 



Now we will take the Dani.-h machine, originally . c o called, although now that there 

 are not one !>u^ four or live machines made in Denmark, we ought 1o follow the example 

 of the. Danes themselves and use the names of the makers: otherwise buyers will some 

 day '.' into a difficulty. This machine, culled, respectively, the IVter-vn and Uurmeis- 

 P<T I'v.- Dam, is sent out by If. C. Pcterseu oc Co.. Copenhagen, which fact should lie 

 . i!lv noted, a-; of the ci^'tit machines we, know (:;::; are made by dili'erent firms of 

 tins name. So fir, this is without doubt the bes! i::.:c!iine vJ.iich has yet appeared. It 

 t-anopm, flat-topped, hori/ontal drum, which nri t h.- fixed upon a su'.id foundation 

 a:,<! c;;n b<- wor);;-d bv one or two horses or bv steam power. The drum is about 'JA 

 le'-t in diameter. <<r 1 ."> inches across the o:>en s| . . v.-hile the depth ii *2 feet. In Die 

 center is a cone, within which is the shaft by which tin- machine is worked. < )n the top 

 or Icdi/e of Die outside drum i < an apparatu- inveijter! by J'rofessor I'jord. of Copenhagen, 

 and int' this the mill: runs a> it comes from tb" vai : here are a set of strainers, and in 

 e;ieb corner tub's '-o ;;iran;_ r ''d tb.it just as much mill; can be passed through as is neces- 

 Ivieh tube extends to very nearly the floor of t he drum ; it is bent at the end so 

 tlia 1 a- tin- milk le-ive-i i: i' runs directly onto the penpb<-rv. AVhen the drum is in 

 iintion -and it rn\oivf-s only I.-UO times a minute the body of the milk is whirled 

 round, arid immediately become:; a wall lining the periphery of the drum. As in tho 



