THE VOYAGE OF H.M.S. CHALLENGER. 
SlI.TNEv* or TUB 
Set — EvjimiiA- 
nos. 
IlMCAIluXt or A 
TUI So KX Tine 
Mrmoo 
‘M 
I'M. v ;’i •• at-r part of which has been dried up by fire, and the surplus has been 
t, :r .me ! under the influence of lieat. Others allege that the whole of the primitive 
• v iru ing be n submitted to the devouring action of the sun in its revolutions, all 
:!i. ii. an have been removed, and the present ocean is merely a saline and bitter 
r There arc others who assert that the sea is simply the secretions which flow 
in m the earth scorched by the heat of the sun during its constant revolutions. 
S 1 i . \ that the sea is nothing else than the primitive humidity separated from all 
! terrestrial principles, just as fresh water mixed with ashes loses its sweetness 
and r tains a saline taste even after it has been filtered. It is also supposed that in 
v .. tl fr sh nd salt parts were mixed, and that the sun volatilised the fresh portions 
I . u - «- their subtility, be it that it absorbs these parts itself, be it that once arrived 
in hi _ r i r- : where cold condenses them and gives them, so to speak, a new form, they 
« • 1 1 : t n "_r • . second time into water. It is held that water being an element, the molecules 
v 'h i, found in the air and under the action of cold have a soft taste, while the 
n 1 u hid: remain on the land take up a bitter flavour under the influence of the 
v. : h p-not rat- s them. Several learned men have held that the mass of water which 
fl into t he ocean either from the surface of the soil or from subterranean passages, 
1 iv” - •in arriv d at that vast reservoir, has absorbed everywhere the saline principles 
v • i ih discharges into it. It is not to be wondered at, then, that the water of the 
rves dways the same weight and bulk, since the subtile parts, which heat removes, 
- n into dew and water whence arise mountain streams, which fall into rivulets 
v • i u - and flow into the wet places of the land, until they arrive, at last, in the 
• whirlpool of the ocean. It is thus that absolutely none of the water is lost, and 
a; like machines which, drawing water from a river, return it to a rivulet that 
p -- • it again to the river It is evident, from experience, that all humid 
: :t< endowed with a certain relish, having passed through the retort and still, preserve 
in tin a sublimate the same smell and taste, like vinegar, date wine, rose saffron, gilly- 
l! ■ it< , except, however, saline substances, which change the taste and smell, 
p«- dh when they are submitted twice to the operation of fire and the still.” 1 
It will b • seen from this quotation, which may be regarded as a correct resume of 
t - hi, -iv. h-dge of the Arabs on this matter, that Mas‘udl possessed exact notions about 
t p:i. n<.n, na of evaporation, the formation of rain, and, in general, on the aerial 
’. i ! : i t i • . j i of v. at r, and on the saltness and conservation of the same in marine basins, 
i •• - *ion h, no doubt, disfigured by errors; it lacks precision and definiteness, 
• ••• ‘i.. i-iui-'iph - expn - <-d are true, and prove the relative state of advancement of 
\i philosophy. In the closing sentences of the above passage the author explains 
i *ii i of ii ,- tur- by comparison with those which take place in the laboratory. 
I i Pc hel has noted, one of the first occasions on which we meet with this truly 
1 M vi‘u<ll, op. cit., tom. i. ch. xiv. pp 277-280. 
