THE BELFAST ADDRESS. 171 



than those formed by the ink of history, which carry 

 the mind back into abysses of past time, compared with 

 which the periods which satisfied Bishop Butler cease 

 to have a visual angle. 



The lode of discovery once struck, those petrified 

 forms in which life was at one time active, increased to 

 multitudes and demanded classification. They were 

 grouped in genera, species, and varieties, according to 

 the degree of similarity subsisting between them. Thus 

 confusion was avoided, each object being found in the 

 pigeon-hole appropriated to it and to its fellows of 

 similar morphological or physiological character. 

 The general fact soon became evident that none but 

 the simplest forms of life lie lowest down; that, as we 

 climb higher among the superimposed strata, more 

 perfect forms appear. The change, however, from 

 form to form was not continuous, but by steps some 

 small, some great. * A section/ says Mr. Huxley, 

 ' a hundred feet thick will exhibit at different heights 

 a dozen species of Ammonite, none of which passes 

 beyond the particular zone of limestone, or clay, 

 into the zone below it, or into that above it/ In 

 the presence of such facts it was not possible to avoid 

 the question: Have these forms, showing, though in 

 broken stages, and with many irregularities, this un- 

 mistakable general advance, being subjected to no con- 

 tinuous law of growth or variation? Had our educa- 

 tion been purely scientific, or had it been sufficiently 

 detached from influences which, however ennobling in 

 another domain, have always proved hindrances and 

 delusions when introduced as factors into the domain 

 of physics, the scientific mind never could have 

 swerved from the search for a law of growth, or allowed 

 itself to accept the anthropomorphism which regarded 

 each successive stratum as a kind of mechanic's bench 

 41 



