I 
iv. 
beings being themselves in great measure united, the 
laws under which they act must be also in greater or less 
unison—mutually dependant and reciprocally illustrative 
of each other, wherever found. In this way is it shewn 
how the laws of life in one series of beings, illustrate and 
imply those of others, and accordingly how essential is 
the study of every department of organic life to the perfect 
knowledge of the physiology of one. 
With these explanations I hope it will in the first 
instance be seen that the knowledge of principles and laws 
is the legitimate aim of the philosophy of our Science ; 
secondly, that to acquire these, we mustpremise a thorough 
acquaintance with Nature, anatomically and physiologi¬ 
cally; thirdly, that amongst other joreparatory information, 
an extended and extending knowledge of the variations 
discoverable in localities is absolutely essential. Let us 
proceed to remind the reader of the truth of this last obser¬ 
vation, by exemplifying the way in which an acquaintance 
with the Natural History of our locality conduces to the 
development of laws. 
From certain differences in the geography and 
physical condition of localities, the meteorological in¬ 
fluences on living beings as to structure, function, and 
economy, are variable in amount and character in different 
situations; a county exposed as ours is to the effects of 
gales, must needs exhibit differences in its Fauna from 
that of a spot not so affected ; a glance at the list of our 
pelagic birds, will place this truth before the student. 
A locality enjoying a tolerable equality in the temperature 
through the year, will needs shew differences with regard 
both to its plants and animals, from sites where the ex- 
