in Egypt, is a kind of trefoil or clover. Bat when 

 the cattle are fed on hay, and the camels on bruised 

 date-kernels, their excrements are not fit for this pur- 

 pose. 



The nitre of Egypt was well known to the an- 

 cients. It is produced in two lakes near Memphis, 

 One of them is four or five leagues long, and one 

 league broad : the other, three leagdes long, and one 

 and a half broad. In both, the nitre is covered by a 

 foot or two of water. They cut it up with long iron, 

 bars, sharp at the end. And what is taken away, is 

 replaced in one or two years, by new nitre, coming 

 out of the earth. 



5. If iron in melting be carefully purged from its 

 dross, drawn into plates, and plunged red hot into 

 cold w r ater, it grows harder, and is termed steel. But 

 it is considerably softened again, if it is put into the 

 fire, and afterwards left to cool gradually in the air. 



6. Quicksilver differs from all metals, in that it is 

 naturally liquid. Its properties are, 1. It is the hca. 

 Tiest of all bodies, but gold and platina. 2, It is the 

 most fluid of all. The particles even of water, do 

 not divide so easily as those of quicksilver : they have 

 hardly any cohesion. 3. Of all bodies it is divisible 

 into the minutest parts. Being on the fire, it resolves 

 into an almost invisible vapour. But let it be divided 

 ever so much, itstill retains its natures For the va* 

 pours of distilled quicksilver, received in water or on 

 moist leather become pure quicksilver. And if it be 

 mixed with lead or other bodies, in order to be fixed, 

 it is easily by fire separated from them again, and re- 

 duced to its ancient form. 4. It is extremely volatile 

 being convertible into a fume, even in a sand-heat, 

 5. Of all fluids it is in equal circumstances the coldest 

 and the hottest. This depends on its weight ; for the 

 heat and cold of all bodies, is (cseteris paribus) aa 



