304 



Preservation of Food. 



Vol. XII. 



partly antiseptically by the salt, and partly 

 by immersion in the liquid brine. Smoked 

 meats are preserved, partly antiseptically by 

 the empyreumatic acid, and partly by the 

 watery particles being driven off by heat, 

 so that the meat becomes a kind of glue, 

 and the air is excluded. Dry cakes of glue 

 may be preserved any length of time; but 

 if they be moistened to admit the air, they 

 soon putrify. The charqui or jerked beef of 

 Southern America is made into a glue by 

 the heat of the sun, and thus assumes the 

 character of cheese ; decomposing by mites 

 in the same manner. Dried flesh of this 

 kind, mixed with butter or fat, is the pemi- 

 can of North Western America, from which 

 air is thus excluded. Egyptian mummies 

 have the air excluded by bandages. There 

 are various modes in which grain is pre- 

 served, some intentional, some accidental 

 What are called brewers' grains or spent 

 malt, the cowkeepers in the neighbourhood 

 of London seek to preserve by covering them 

 over in pits. The air is not excluded, and 

 therefore the method is inefficient. What 

 is called mummy wheat, has been preserved 

 by the effectual exclusion of the air. In 

 Spain, wheat is preserved in what is called 

 Silos, i. e., underground pits of peculiar soil, 

 covered in with earth. Wheat thus treated 

 lasts many years. The French armies were 

 accustomed to hunt for these deposits for 

 subsistence. A flat stone usually covered 

 the opening ; and on its removal a quantity 

 of deleterious gas generally rushed out, 

 sometimes killing the opener with asphyxia 

 In Canada West, hunters and Indians make 

 deposits of corn and other things in artificial 

 caverns called Caches, chosen in dry spots, 

 and covered over. In some of the interna 

 parts of Spanish America, the common gran- 

 ary is the skin of an ox taken off entire, and 

 the legs and neck being tied round it, is filled 

 with tightly-rammed earth through a hole in 

 the back, while suspended between posts, 

 When dried to a state of parchment, the 

 earth is taken out, and the bloated bag, re- 

 sembling a huge hippopotamus, is filled with 

 grain, which is thus kept air and vermin 

 proof. 



Three conditions are essential to the pro- 

 cess of putrefaction; viz.: heat, moisture, 

 and still air. With wind, moisture is car- 

 ried off; with cold, the decomposing process 

 is checked, as may be seen by the carcases 

 of animals that lie through the winter in 

 snowy mnnntains, and dry up to glue. With- 

 out air, everything is locked up and remains 

 in statu quo; as reptiles have been buried 

 for ages in blocks of stone or ancient trees, 

 and then resumed their vital functions, un- 

 changed by time. 



In direct opposition to these principles are 

 the granaries of Great Britain and other 

 countries constructed. Their site is gene- 

 rally the bank of a river, or the sea-side. 

 They are built of many floors at a vast ex- 

 pense. They are provided with many win- 

 dows, each floor being the height of a man, 

 yet not permitting more than twelve to fif- 

 teen inches depth of grain on each floor, for 

 fear of heating, unless in the case of very 

 old samples. Men are continually employed 

 to turn the grain over, to ventilate it, and 

 clear out the vermin; and the weevil is na- 

 turalized in every crevice, as surely as bugs 

 in neglected London beds, or cockroaches in 

 West Indian sugar ships. It is the admis- 

 sion of air that permits this evil, that pro- 

 motes germination, that permits the exist- 

 ence of rats and mice. In the exclusion of 

 air is to be found the remedy. The practi- 

 calization of this is neither difficult nor cost- 

 ly: on the contrary, close granaries might 

 be constructed at far less proportional cost 

 than the existing kind. They might be 

 made under ground as well as above ground, 

 in many cases belter. They might be con- 

 structed of cast iron, like gasometer tanks; 

 or of brick and cement; or of brick and as- 

 phalte, like underground wafer-tanks. It is 

 only required that they should be air-tight, 

 and consequently water-tight. A single 

 man-hole at the top, similar to a steam 

 boiler, is all the opening required, with an 

 air-tight cover. The air-pump has long 

 ceased to be a philosophic toy, and has 

 taken its place in the arts as a manufac- 

 turer's tool ; and no difficulty would exist as 

 to that portion of the mechanism. Now, if 

 we suppose a large cast-iron or brick cylin- 

 der sunk in the earth, the bottom being con- 

 ical, and the top domed over; an air-pump 

 adjusted for exhausting the air, and an Ar- 

 chimedean screw pump to discharge the 

 grain, we have the whole apparatus com- 

 plete. If we provide for wet grain, a water- 

 pump may be added, as to a leaky ship. 

 Suppose, now, a cargo of grain, partly ger- 

 minating, and containing rats, mice, and 

 weevils, to be shot into this reservoir, the 

 cover put on and luted, and the air-pump at 

 work, the germination would instantly cease, 

 and the animal functions would be suspend- 

 ed. If it be objected that they would re- 

 vive with the admission of the air, we an- 

 swer, that the air need not be admitted, save 

 to empty the reservoir. If it be contended 

 that the reservoir may be leaky, we answer 

 so may a ship; and if so, the air-pump must 

 be set to work just as is the case with a 

 water-pump in a leaky ship. 



The cost of an underground reservoir 

 would possibly be more than one above 



