THE VICTORIAN XATUEALIST. 23 



limits between which their sizes lie, and Professor Maxwell 

 says — " Natural causes we know are at work which tend to 

 modify, if they do not at length destroy, all the arrangements 

 and dimensions of the earth and the whole solar system. But 

 though in the course of ages catastrophes have occurred, and 

 may yet occur, in the heavens, though ancient systems may be 

 dissolved, and new systems evolved out of their ruins, the 

 molecules out of which these systems are built, the foundation- 

 stones of the material universe, remain unbroken and unworn." 



Astronomy has had its triumphs, too. In this science what 

 has struck my mind most has been the discoveries of the 

 spectroscope. In far off times Egyptian and Arab noted well 

 the heavenly orbs and tracked their courses, but, true though it 

 be, it seems incredible that hundreds of millions of miles away 

 we can tell with certainty what gases burn, what metals are in 

 fusion in those far off suns. Concerning this Professor Huxley 

 says in his last address to the Royal Society : — " What an 

 enormo'us revolution would be made in biology if physics or 

 chemistry could supply the physiologist with a means of making 

 out the molecular structure of living tissues, comparable to that 

 which the spectroscope affords to the inquirer into the nature 

 of the heavenly bodies. At the present moment the constitu- 

 tion of our own bodies are more remote than those of Sirius in 

 this respect." 



Brilliant, however, as have been the results attained by the 

 spectroscope, the greatest triumph yet achieved, perhaps, by the 

 human intellect was the almost simultaneous discovery by 

 Leverrier and Adams of the planet Neptune — a discovery that 

 was made by a process of pure deductive reasoning — made by 

 calculation in the study, the telescope being merely directed 

 to the spot in the heavens where the astronomer declared the 

 planet must be. 



With respect to light, heat, magnetism, and electricity 

 almost all our present knowledge of them has been acquired 

 since her Majesty ascended the throne. 



As for the art of photography, the power to use the magic 

 hand that draws for us, without error, the faces of our friends, 

 sketches the beauties of our mountains and our vales, our 

 forests and our streams, the way to use this power for practical 

 purposes has all been learnt in this same epoch. 



Time would fail me to tell of the changes that have taken 

 place in the classification of plants and animals, and the new 

 forms that have been discovered in earth, and air, and sea. 



But it is, perhaps, in what has been called the "generalisations 

 of science" that this reign has been so brilliant. Of these 

 generalisations, two, by common accord, are assigned chief 



