10 



Eggs can only become " bad," when stored beneath the surface of a 10-per-cent. 

 solution of water-glass, from the activity of micro-organisms already within their 

 shells before preservation. 



The object of storing crackers and cakes in tightly closed tins is, of course, the 

 exclusion of moisture. Similarly, sugar, tea, and other groceries are kept in tin-lined 

 or earthenware utensils. 



Hams, bacon, or smoked meats or fish should be put into cheese-cloth or linen 

 bags before being hung in a dry, well-ventilated place. 



Apples, lemons, tomatoes, and similar fruits should be wrapped separately in soft 

 paper after wiping, and stored on airy shelves, which may be covered with straw or 

 chaff or sawdust. 



The reason for this care, which to some may seem superfluous, lies in the channels 

 by which the germs of decay or the seeds of moulds reach the foodstuffs they destroy. 



The two channels of primary importance, and those only to which reference can 

 here be made, are : 

 (a.) The air. 

 (b.) Flies. 



(a.) THE AIR. 



It has already been pointed out that these mischievous atoms of microscopic life, 

 the organisms of decay, are always present in the atmosphere, with the exception of 

 mid-ocean and the summits of very high mountains. 



When the air travels fast, they are rushed along in its currents; but so soon as it 

 is still the micro-organisms, with the dust of which they form an ingredient, gradually 

 drop down on to the surrounding surfaces. 



If these be moist and the air be warm, the chances are the seeds of decay will 

 begin to grow. They will certainly do so if the substance on which they settle is one 

 on which they can feed. 



Now, invisible moisture collects in the "pits" round the eyes or stems of fruit 

 such as apples, pears, or tomatoes ; or in any dent in their skins, or in the crevice 

 where two fruit rub shoulders. 



Porous Paper a-s a Fruit-preservative. 



Soft porous paper wrappings serve a double purpose. They absorb moisture from 

 the air before it reaches the fruit at all, and by covering the fruit the}' prevent germs 

 or moulds from falling on to its surface. 



(6.) FLIKS. 



In conclusion, a few words must be said about the great importance of the protection 

 of food from flies, which are known to be a fruitful source of disease in food as well as 

 a channel by which the sources of decay menace its soundness and sweetness. 



"Fly-spots" consist of the saliva and excrement of flies, as they pass impartially 

 from cow-dung or night-soil to the baby's milk or the family sugar or cake. It is not, 

 therefore, surprising that the fly is now shunned as one of the chief carriers, not only of 

 dirt and decay, but of the infection of typhoid fever, tuberculosis, and other dangerous 

 diseases. 



The Structure af a Fly and it* Haldt* 



adapt it peculiarly for the conveyance of filth, in addition to the micro-organisms which 

 swarm these "fly-spots." The six, many-jointed legs are densely hairy, and each leg 

 terminates in a pair of hooks, with a "glue-pad" attached to each hook. A glance at 

 Fig. (10) will make clear the enormous power possessed by a fly for carrying tilth from 

 the unclean to the clean. 



