a Theory of the Earth. 221 
with him fome falt or pickled meat; but M. Parmentier’s 
faloop of potatoes, with cakes of portable foup, and bread, 
will form the moft nourifhing food,, and what may be con- 
tained in the Jeaft room. A {mall iron chaffing-difh, a finall 
bag filled with charcoal, and a pan of tinned copper or iron, 
form my kitchen apparatus for the mountains: wooden plates 
and fpoons may be found in the remoteft huts. It will be 
proper, however, to carry always in the pocket a cup of 
gum elafiic, in order that the traveller may at all times eafily 
quench his thirft, a want to which he will be frequently ex- 
pofed in his excurfions. 
From what has been faid, it may be readily feen, that the 
fiudy of geology will not fuit the indolent or fenfual; for the 
life-of the geologue muft be divided between fatiguing and 
perilous journies, in which he is deprived of almoft all the 
conyeniences of life, and the varied and deep refearches of 
the clofet. But what is ftill more rare, and perhaps more ne-= 
ceffary than the zeal requifite to furmount thefe obftacles, is, a 
mind free from prejudice; filled with an ardent defire for the 
truth alone, rather than with a defire for raifing or deftroying 
fyftems; capable of defcending to minute details indifpenfibly 
neceflary for the correCtnefs and certainty of obfervations, 
and of rifing to grand views and general conceptions. Thofe 
fond of fuch fudies, ought not, vacipeaaene to be difcouraged 
by thefe difficulties ; there is no traveller who may not make 
fome good-obfervation, and bring with him at leaft one ftone 
worthy of being employed in the con{truction of this grand 
edifice. It is indeed poffible to be ufeful without attaining 
to perfection ; for I have no doubt that if the mineralogical 
travels, even the moft efleemed, and much more thofe of the 
author, be compared with thefe Agenda, there will be found 
in them many deficiencies, and many obfervations, either im- 
perfect, or even totally forgotten: but I have mentioned the 
reafon in the Introduction. Befides, feveral of thefe ideas 
did not occur till I had finifhed my travels; and for that rea- 
fon T laboured with more zeal on thefe Agenda, in the hope 
of rendering young perfons, on their entering this career, 
‘capable of performing what coft. me thirty-fix years of tra- 
yelling and ftudy, 
: 
Ill. Ox 
