which it costs him to regain his footing — if, indeed, he shall ever regain it at all — 

 would, with proper heed to his steps, have carried him far onward upon his jour- 

 ney. 



Besides, those " stars" of genius follow the law of all other stars, by being con- 

 spicuous only in the dark, and more conspicuous the more profound the obscurity is, 

 and the more vacant the space athwart which they are seen. In the mighty dark- 

 ness of those ages, during which the combined mischief of reckless war, and sense- 

 less superstition, had well-nigh banished science from the earth, a single scintilla- 

 tion, and that too of some false light — of some ignis fatuus of the polluted air — 

 was sufficient to constitute a star of the first magnitude, after which the benighted 

 children of men wondered and worshipped ; and this they were prone to endow 

 with " airs from heaven" or " blasts from hell," upon as slender grounds as those 

 which called forth their wonder and their worship. But as the dawn of true 

 knowledge broke, and the sun of science neared the horizon, the stars in that part 

 waxed dim and disappeared ; and when this glorious morning to the human mind 

 had so far advanced as to shew, as it were, to the great body of the people upon 

 the earth the objects immediately around them, in their true colours, so that each 

 man might observe with his own senses, and judge with his own understanding, 

 those stars of the darkness of intellectual night vanished away, as is the case with 

 their namesakes of the natural sky. 



We do not say that the full light of the sun of knowledge has yet broken upon 

 even the most lofty pinnacles of human nature ; but we do say that the morning 

 dawn is both broad and glorious ; so that any one who has eyes to see, and will 

 use them, may fully understand everything which comes within the range of his 

 observation, and within the legitimate pale of human philosophy. And it is pre- 

 cisely because such is the case — because the light of science is general, and sets 

 off the qualities and the nature of things by their coincidencies and their contrasts, 

 it has become so necessary thoroughly to understand the general nature of this 

 light, before we proceed to the details of those subjects which it reveals to us. 



The illustrations which we may draw from this analogy of the light of Nature, 

 and of the light of Science, especially of the science of Nature, are very numerous, 

 and they are equally apt and striking. It is the light itself which reveals to us 

 the forms of things, and which paints them with all their varied colours. In the 

 blackness of darkness, the most lovely flower, or the richest parterre, is a mere 

 blank ; and if we examine objects by means of a decomposed light, or through a 

 tainted or coloured medium, the false colour of the light, or the taint of the me- 

 dium, disguises all that we see ; just as looking through a red glass makes the 

 whole landscape red ; or as the murky air, by turning aside all the more refrangi- 

 ble colours of the solar beam, makes the cloud, and even the sun itself, seem 

 murky. Those matters were not understood until men knew how to divide 

 the white light of the sun into its component shades. But when once this was 



