Chap. 106.] WOKPEKS Or rOTJNTATNS AISTD EIYEES. 137 
these other wonderful operations of nature ; that copper and 
lead sink when in a mass, but float when spread out^ ; and 
of things that are equally heavy, some will sink to the bot- 
tom, while others will remain on the surface^ ; that heavy 
bodies are more easily moved in water^ ; that a stone from 
Scyros, although very large, will float, while the same, when 
broken into small pieces, sinks'^ ; that the body of an animal, 
newly deprived of life, sinks, but that, when it is swelled 
out, it floats^ ; that empty vessels are drawn out of the water 
with no more ease than those that are full^ ; that rain-water 
is more useful for salt-pits than other kinds of water^; 
that salt cannot be made, unless it is mixed with fresh water ^ ; 
that salt water freezes with more difiiculty^, and is more readily 
heated^^ ; that the sea is warmer in winter" and more salt in 
1 Tkm leaves or films of metal have little affinity for water, and have, 
generally, bubbles of air attached to them ; so that, v^^hen placed upon 
the water, the fluid is prevented from adliering to them, and thus they 
remain on the surface. 
2 Depending not upon their absolute, but their specific gravity. 
3 Being partly supported by the water. 
^ The stone may have floated in consequence of its being full of pores : 
these are more .quickly fiilled with water when it is broken into small 
pieces. It was probably of the nature of pumice or some other volcanic 
product. 
^ This is well known to depend upon the commencement of the de- 
composition of some part of the viscera, by which there is an evolution 
of gaseous matter. 
^ This is an erroneous statement ; it is not easy to ascertain what was 
the source of the error. 
7 E-ain, as it falls, from the clouds, is nearly pure ; and rivers, or recep- 
tacles of any kind, that are supphed by it, are considerably more free from 
sahne impregnations than the generality of springs. 
s Tliis statement is altogether incorrect. 
9 When salt water freezes, it is disengaged from the saline matter which 
it previously held in solution ; a greater degree of cold is therefore re- 
quired to overcome the attraction of the water for the salt, and to form 
the ice, than when pure water is congealed. 
" Celerius accendi." We can scarcely suppose that by this term our 
author intended to express the actual burning or inflaming of the water, 
which is its hteral and ordinary meaning. This, however, would appear 
to be the opinion of Hardouin and Alexandre ; Lemaire, i. 449. Holland 
translates it, "made hot and set a-seething," i. 46 ; Poinsinet, " s'echaufle 
le plus vite," i. 313 ; and Ajasson, " plus prompte a s'echauffer," ii. 217. 
The temperature of the ocean, in consequence of its great mass and 
ihd easy dLOTusion and mixture of its various parts, may be conceived to 
