TIME, SPACE, AND INVISIBLE WORLDS. 237 



might change at any hour. Thus, the natural order of everything 

 might at any moment be reversed, Earth become mad, and its 

 inhabitants lunatics. Only thus, by extreme contrast, can we 

 properly estimate the immense value and importance to us, of this 

 law of Continuity throughout the Universe. Man finds in this 

 Continuity his promise and warrant, that, " if he depend upon 

 nature, his intellect shall not be insulted, nor his confidence 

 abused ; " and " if man has to trust nature, that his reason shall 

 not be put to confusion." Continuity, it has been well said, " is 

 the expression of the Divine veracity in nature." 



Assuming, then, a universal oneness in nature, we should 

 expect to find, as -discovery progresses, a general harmony between 

 truth known and truth not known ; and that the great lines of 

 natural laws, which prevail throughout, and (if we may speak of law 

 as a governing agent) regulate our Solar System, are not only 

 similar to, but identical with, those which exist throughout the 

 Stellar Universe ; and which we may liken to those artificial lines 

 of longitude and latitude by which we explain the positions and 

 movements, equally of near planets and distant stars. Following 

 Newton's discovery in 1686, of gravitation, the greatest generalisa- 

 tion the world has yet seen, SirWm. Herschel startled the scientific 

 world in 1802, with the announcement that amongst the Stars, 

 binary systems exist, in which the smaller star revolves in circular 

 or elliptical orbit round the larger. There was no mistaking the 

 meaning of this discovery. Here was ocular demonstration of 

 Continuity— viz. : that the same law which causes the apple to fall 

 to the ground, which retains the Moon in her orbit, and restrains 

 our Earth from its otherwise headlong flight away from the Sun, 

 also controls and regulates those giant orbs in remote space. 



Up to recent years. Astronomers had assumed certain truths 

 about the Stars, but were without demonstrable evidence on the 

 following points : — i. Constitution of the Stars. 2. Are they in- 

 candescent, and from what does their light proceed ? Are any 

 Stars motionless in space ; or, in other words, do exceptions exist 

 in outer space, to that law of Motion in matter, which appears to 

 obtain throughout the Universe ? In putting these questions to 

 spectrum analysis, an opportunity now offered of proving or dis- 

 proving, the continuity, throughout the Universe, of Solar or 



