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content ourselves by simply promising that, while much importance 

 attaches to the purity of water used in culinary and other operations, we 

 cannot but think the reports just alluded to have been exaggerated, and 

 the subject greatly overdrawn, and are calculated to produce disgust 

 without any adequate benefit. The softest water pi-ocurable should be 

 used for all culinary purposes, but in manufactures it is often found 

 desirable that a proportion of mineral salts should be present. This is 

 especially the case in the brewing of beer and manufacture of vinegar ; 

 and hence, that water which contains the largest proportion of sulphate 

 of lime produces the best and most persistant results ; arising, no doubt, 

 from the antiseptic properties of that salt. 



The purest water for culinai'y purposes may generally be drawn from 

 the clouds ; rain water filtered and boiled is of great purity, but is sub- 

 ject to much greater contamination from the vessels it is contained in, 

 (if they be of metal,) than the hardest spring water would be. Not long 

 since an instance of this kind came under our notice. A sample of 

 rain water from a suburb of this town was bi'ought to me for analysis, 

 very alarming symptoms having been produced in those who had been 

 consuming it. We were not long in discovering a very decided quantity 

 of lead, derived from the leaden tank it was collected in on the roof of 

 the house ; and this is invariably the result, in a greater or less degree, 

 of storing rain water in leaden cisterns. Hard spring waters, on the 

 contraiy, and especially those containing sulphate of potass, would exert 

 but a very slight action upon the metal. Thus we see, that while rain 

 water, when kept in non-metallic vessels, is the best suited for the pre- 

 paration of food, when stored in metal reservoirs it is far more Hable 

 than the hardest water to become contaminated, and in time positively 

 poisonous. 



Farinaceous substances form by far the largest proportion of our diet, 

 and therefoi'e we will first examine 



Flour and Bread. 

 Flour should consist of finely ground wheat, freed from its adhering 

 husk. Such, Dr. Hassal tells us, he found to be the case with all the 

 samples he examined. 



In the examination of flour and other organic substances of a like 

 nature, the chemist, unaided by the microscope, is almost powerless to 

 determine the admixture of inferior kinds with the more valuable ; we 

 have therefore, throughout our examinations, combined a microscopical 

 with a chemical analysis. 



Flour may be adulterated with mineral substances, such as gypsum, 

 chalk, alum, salt, &:c., or with inferior farinaceous substances, such as 



