MILK 



MILKY WAY 



Mn K preservative*) as formalin, 



or IH.IU- Jii-i.l. ii highly undesirable 



, All germs can be 



-il by exposing the milk 



to it I;; i temperature to 



cause Ht-nlis:iiioii, but the pro- 



lo tho health of 



. iiil.li-rii iiiui has an unpleasant 

 <l taste, due to the burning 

 i>t ili.- milk sugar. A better plan is 

 pasteurisation, by which disease 

 L'< mis are destroyed, and those 

 which interfere with butter or 

 cheese making are kept in check. 

 'I'll.- milk of goats is practically free 

 from the germs of tuberculosis. 



Condensed milk is the npjie 

 _i\i n to milk from which moat of 

 the water has been removed by 

 evaporation at a comparatively 

 low temperature and in a partial 

 vacuum. In 1850, de Leinac, a 

 Fn-ru -liman, succeeded in evapor- 

 ating milk in an open pan, but the 

 method now widely in use was 

 patented in 1856, in America, by 

 Gail Borden. Sugar may or may 

 not be added, and the finished 

 product is usually kept in herme- 

 tically sealed tins. 



Milk powder or desiccated milk 

 was known as an article of com- 

 merce as far back as 1870. In 

 essence the process consists in 

 drying the milk on steam -heated 

 i ylimlers. The milk is obtained 

 from tuberculin-tested cows and 

 is filtered through a special filter 

 to remove the dirt, cooled and 

 kept at a low temperature in in- 

 sulated vats. The cows are 

 milked by machinery which de- 

 livers the milk into closed vessels. 

 The milk is tested for its total 

 solids and standardised by the 

 inMition of lactose and butter- 

 fat, and the drying process 

 rapidly carried out. 



MILK TESTS. Careful analysis 

 of a large number of samples of 

 whole milk, taken during the 

 different months of the year, give 

 as an average : percentage of total 

 solids, 12*63, consisting of fats, 

 3 75 and non-fats, 8'88 ; specific 

 L-ravity, T032. The legal standard 

 as laid down in the Sale of Food 

 and Drugs Act, 1899, is 3 p.c. fat 

 and 8*5 p.c. of non-fatty solids. It 

 is established, however, that un- 

 adulterated milk often falls below 

 the fat standard thus laid down. 



The specific gravity of milk is 

 usually determined by a lacto- 

 meter. More accurate results are 

 obtained by the Westphal balance, 

 a kind of small steelyard with a 

 weight that is suspended in the 

 milk to be tested. In either case 

 the specific gravity must be taken 

 at 60 Fah., or a correction made 

 if the temperature is higher or 

 lower. The amount of butter fat 

 is most speedily determined by the 



Gerber centrifuge, in which small 

 test bottles are whirled round at a 



!J!.-,lt .-|H'<-<1. Kiirli linttli- I- pro 



vided with a narrower tubular 

 portion that is turned towards the 

 centrifuge, and in which the fat 

 collects. Before being placed in 

 the machine the test oottle is 

 filled with 10 cubic centimetres of 

 dilute sulphuric acid (sp. gr. I '820 

 to 1-825), 11 c.c. of milk, and 1 

 c.o. of amyl alcohol. The acid dis- 

 solves the non-fatty solids, the fat 

 being separated in an oily form, a 

 process that is helped by the 

 alcohol. Given the fat percentage 

 and the specific gravity, it is 

 possible to calculate the total 

 solids by means of a formula. See 

 Butter; Cattle; Cheese; Dairy 

 Farming; Diet; Public Health; 

 consult also Milk and the Public 

 Health, W. G. Savage, 1912. 



Milk. River of Canada and the 

 U.S.A. Rising in the Rocky Mts. of 

 Montana, near the Alberta boun- 

 dary, it flows E. through Alberta 

 for about 200 m. and then for a fur- 

 ther 300 m. through Montana to the 

 Missouri. 



Milking. The process of ex- 

 tracting milk from the cow or goat. 

 Usually it is done by hand labour, 

 but machinery is now being used 

 for the purpose. The udder of the 

 cow consists of four separate sec- 

 tions or quarters, two fore and two 

 hind, each of which is discharged 

 from a teat of its own. In the 

 ordinary English method the 

 operator sits down after speaking 

 to the cow, and begins with the 

 fore quarters, grasping the teats 

 part of the way round and press- 

 ing them against the palms by 

 the finger tips. The pressure 

 should be horizontal and applied 

 at regular intervals, and the 

 fingers must be kept on the teats 

 until the fore quarters have been 

 emptied. The movement must 

 come from the wrists and not the 

 elbows. The hind quarters are then 

 treated in the same way, and 

 when they are finished the fore 

 quarters should be stripped again. 

 The Danes ensure the final strip- 

 ping of the udder by a rather 

 elaborate kind of massage (Hege- 

 lund system). 



On farms where a large number 

 of cows are kept it is becoming 

 increasingly the practice to milk 

 by machinery, as this saves 

 labour and promotes cleanliness, 

 always provided the machine 

 itself is kept scrupulously clean. 

 The ordinary principle combines 

 suction with pressure, and there 

 should be a rhythmic or pulsating 

 action. See Dairy Farming ; Egypt. 



Milk Sugar. Variety of sugar 

 found in milk. It is obtained by 

 evaporation after the removal of 



MUkwort. Flower* 



ing stems of the 



meadow herb 



the fat and casein. Milk sugar ap- 

 pears aa sweet, rather gritty cry Utah, 

 partly soluble in water, and i used 

 in pharmacy. It u not so aweet M 

 cane sugar, and 

 chemically i 

 better known 

 under its alter- 

 native name of 

 lactose (q.v.). 



Milkwort 

 (Polygala vul- 

 grarwJoR ROGA- 

 TION FLOWER. 

 Perennial herb 

 of the natural 

 order Poly 

 galaceae. A 

 native of Eu- 

 rope (including 

 B ritain), N. 

 Asia, and N. 

 Africa, it has 

 short, wiry stems and somewhat 

 leathery, oblong leaves. Its flow- 

 ers are white, pink, blue, or purple. 

 It grows among grass in meadows 

 and on heaths, and cows eating it 

 were formerly supposed to yield 

 more milk than ordinarily. 



Milky Way. In astronomy, 

 name given to the luminous band 

 which appears to stretch across 

 the sky at night. To the naked 

 eye appearing a vast zone-shaped 

 nebula, it appears through a tele- 

 scope to consist of innumerable 

 stars. Its stellar constitution, con- 

 jectured by Democritus, was one 

 of Galileo's earliest telescopic 

 discoveries. 



A line drawn midway through it 

 lies nearly on a great circle inclined 

 about 63 to the celestial equator. 

 It passes, in Cassiopeia, within 27 

 of the North Pole of the heavens 

 and, in the Southern constellation 

 of the Cross (Crux), equally near to 

 the South Pole, while its own poles 

 are in the constellations of Coma 

 Berenices and Cetus. For over two- 

 thirds of its circuit in the skies it 

 preserves an appearance of unity. 

 But near Alpha Centauri it is 

 broken by a great fissure into two 

 branches, one faint and the other 

 bright, which rejoin in the neigh- 

 bourhood of Eta Cygni. This rift 

 between the branches is, however, 

 nowhere free from fringes, bridges, 

 filaments and pools of starry 

 spaces. There is yet another inter- 

 ruption to the Milky Way, in the 

 constellation of Argo, where the 

 undivided stream is cut across by 

 a jagged chasm, with interlacing 

 branches on either side. ^ 



The Milky Way is not a uniform 

 starry strca'm. The elder Herschel 

 counted many luminous patches in 

 it ; his son compared it to " clouds 

 passing in a scud " ; and to sand 



not strewed evenly as in a sieve, 

 but as if flung down by handfuls, 



