OF THE MARSH POISON. 289 



bon, and throughout Portugal, there can be no gardens with- 

 out water ; but the garden is almost every thing to a Portu- 

 guese family. All classes of the inhabitants endeavour to esta- 

 blish and preserve them, particularly in Lisbon, for which pur- 

 pose they have very large stone reservoirs of water, that are 

 filled by pipes from the public aqueducts, when water is abun- 

 dant ; — but these supplies are always cut off in the summer. 

 The water, consequently, being most precious, is husbanded 

 with the utmost care for the three months absolute drought of 

 the summer-season. It falls of course into the most concen- 

 trated state of foulness and putridity, diminishing and evapo- 

 rating day after day, but never absorbed, till it subsides either 

 into a thick green vegetable scum, or a dried crust. In the 

 confined gardens of Lisbon particularly, these reservoirs may 

 be seen in this state close to the houses, even to the sleeping 

 places of the household, in the atmosphere of which they lite- 

 rally live and breathe ; yet no one ever heard or dreamt of fe- 

 ver being generated amongst them from such a source ; though 

 the most ignorant native is well aware, that were he only to 

 cross the river, and sleep on the sandy shores of the Alentejo, 

 where a particle of water at that season had not been seen for 

 months, and where water being absorbed into the sand as soon 

 as it fell, was never known to be putrid, he would run the 

 greatest risk of being seized with remittent fever. 



From all the foregoing, the deduction appears to be unque- 

 stionable, that endemic fevers cannot be generated either from 

 aqueous or vegetable putrefaction, singly or combined. It ema- 

 nates, as we have seen, from the shores of the purest streams, 

 wherever they have been flooded during the rains, through 

 want of confining banks, and it is absent from the most putrid 

 waters. It must be impossible that healthy living water, which 



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