i4 NUTRIENTIA. Art. I. 2. 4, 1. 



By the future improvements of human reafon fuch govern- 

 ments may poflibly hereafter be eftablilhed, as may a hundred- 

 fold increafe the numbers of mankind/and a thoufand-fold their 

 happinefs. 



IV. 1. Water muft be confidered as a part of our nutriment, 

 becaufe fo much of it enters the compofition of our folids at 

 well as of our fluids ; and becaufe vegetables are now believed to 

 draw almoft the whole of their nouriihment from this fource. 

 As in them the water is decompofed, as it is perfpired bv them 

 in the funihine, the oxygen gas increafes the quantity and the 

 purity of the atmofphere in their vicinity, and the hydrogen 

 feems to be retained, and to form the nutritive juices, and cou- 

 fcquent fecretions of refin, gum, wax, honey, oil, and other vcg- 

 eruble productions. See Botanic Garden, Part I. Cant. IV. 

 line 25, note. It has however other ufes in the fyftem, befides 

 that of a nourifhing material, as it dilutes our fluids, and lubri- 

 c ttes our folids ; and on all thefe accounts a daily fupply of it is 

 required. 



2. River-water is in general purer than fpring-watcr ; as the 

 neutral falts warned down from the earth decompofe each other, 

 except perhaps the marine fait ; and the earths, with which 

 fpring-water frequently abounds, is precipitated ; yet it is not 

 improbable, that the calcareous earth dilTolved in the water of 

 many fprings may contribute to our ncurifhment, as the water 

 from fprings, which contain earth, is faid to conduce to enrich 

 thole lands, which are flooded with it, more than river water. 



The Chinefe are faid, by Sir G. Staunton, to purify the water 

 cf fome muddy rivers or canals, by ftirring them with a hollow 

 cane full of fmall holes, in the tube of which are enclofed fome 

 pieces of alum. And the bakers in London afot, that one ufe 

 of alum is to clear the New River water, and thus to render 



:ir bread whiter. Where any volatile alkali is mixed with 

 water, as often happens from the liable dung and other ordure 

 of populous towns, it will be converted to vitriolic ammoniac by 

 a folution of alum : and calcareous earth mav be converted into 

 gypfum, and fubfide along with the earth of the alum. See 

 Clafs II. 1. 6. 16. * 



3. Many arguments feem to fhew, that calcareous earth con- 

 tributes to the nouriihment of animals and vegetables. Firft 

 becaufe calcareous earth conftitutes a confiderable part of them, 

 and muft therefore either be received from without, or formed 

 by them, cr both, as milk, when taken as food by a laclefcent 

 woman, is decompofed in the (lomach by the procefs of digef- 

 tion, and again in part converted into milk by the pectoral glanc 

 Secondly, becaufe from the analogy of all organic life, whatever 



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