75 
law of gravitation has been proved, and more than proved, by 
the researches of the last two hundred years. But there cluster 
around it, even now, some of the wildest fancies that ever 
entered the mind of man. Matter certainly exists; though 
this is denied by some philosophers, and others balance the 
error by asserting that nothing exists beside it. But the 
views of its true nature are so diverse as almost to bring into 
doubt the very fact they seek to explain. Ether also exists; 
though here the doubters have more excuse, and are more 
numerous. But the contrast and variety in opinions as to 
its precise nature are greater still. Conservation of energy 
is a truth, inductively proved within certain limits, and in 
reference to lifeless matter and ether in all their forms. But 
some affirm it to be the first of a priori truths, far more certain 
than the Being of God. And they extend it to all living 
things ; which involves the singular doctrine that men and 
animals must like or dislike all things in a strictly equal degree, 
whenever they are at the same distance. Others retain in 
words this ci’eed of the conservation of energy, but replace it 
really by the counter-doctrine of its ceaseless dissipation and 
loss. The concussion theory of solar heat has been taken up 
and abandoned within the last twenty years. The contraction 
theory is now in vogue, but cannot fail to share the fate of its 
short-lived predecessor. The molten nucleus theory of the 
earth's structure has reigned for two or three generations, 
and is now finally disproved. The astro-glacial theory, born 
only the other day, has no stamina of life, and will probably 
die to-morrow. The teaching of the elder Herschel on the 
distribution of the stars is being fast superseded, through 
the reasoning of his no less eminent son on the Magellanic 
clouds, and by other still later discoveries. The words of 
Cato in Addison apply even to this clearest part of this scientific 
landscape : 
A wide, unbounded prosjjeet lies before me, 
But shadows, clouds, and darkness rest upon it. 
As a general rule, those speak most boastfully of the 
achievements of modern science who understand them the 
least ; and those impute credulity to Christian believers most 
freely, who are practising it themselves in a more aggravated 
form. They will not believe the Scriptures to be really the 
word of God, though confinned by miracles and prophecies, 
and the experience of tens of thousands, who have found them 
to bring moral strength, and deep and lasting peace to their 
inmost souls. But they can accept with implicit faith guesses 
