BY MOLECULAR COALESCENCE. 151 
and unceasingly in action, would require no fresh arrange- 
ment of conditions necessary for its production, whilst the 
former being entirely a local influence, and exerted for one 
purpose only, and with an effect varying at every instant, 
would require the chemical condition upon which it depends 
to be also constantly varying. Now, in the formation of the 
erab- and oyster-shell these conditions, and the manner in 
which they operate, are toa very great extent apparent ; but 
in the case of the formation of the material composing the 
lens, the chemical process is not, at least in the present 
state of science, at all clear; and doubtless a most exact 
chemical investigation, directed especially to this point, 
would be required to make it so. However, one question 
presents itself, whether, is that which has the power of bring- 
ing together these conditions, chemical and mechanical, and 
exactly adapting them to the necessities of the case, resi- 
dent im and exercised by the material of the lens? or, 
whether it is the effect of a separate and independent 
principle, acting upon this material, through the instru- 
mentality of well-known influences, called the properties of 
matter? If the aflirmative is to be given to the first part 
of this question, then I cannot see how it is possible to 
deny the existence of an amount of intelligence and skill 
in the cells of the lens of the eye of any being, infinitely 
surpassing that of the individual to which it belongs. For 
how could the particles composing these globules so regulate 
their densityand curvature, that all the rays passing through 
them should be brought colourless to one point, without 
possessing a perfect knowledge of the laws of dispersion and 
refraction of light? or, how could the developing particles, 
occupying similar points on opposite sides of the axis of 
the same lens, or points having precisely the same relative 
position in the lenses of both eyes, preserve always a like 
