46 National Institviions for [Jan., 



commonly prove to be the first steps to deductions and discoveries 

 tliat revolutionize the conditions of civilized society. Every point 

 that occurs as involving some insufficiently examined element, 

 must Ije viewed as a herald that promises to increase and compact 

 man's knowledge of law and his i:)ower over material nature. No 

 one who had chanced to observe the Bologna Professor of Ana- 

 tomy's pretty and apparently somewhat puerile dealing \dih the 

 contractions of dead frogs, could ever have conceived that there was 

 in those experiments the first stej) towards the utihzation of a power 

 which was waiting the bidding of human intelligence to cover the 

 earth with a network of instantaneous communication, and to en- 

 able men to converse and consult together with safety and ease, 

 while boisterous oceans of thousands of miles' span were heaving 

 between them. If the lead of Galvani's experiment had not been 

 tracked out as it was, electric telegraphy would most probably 

 still have been an art of the future. But if there had l^een in 

 Galvani's days more adequate pro\asion for seizing and following 

 out that lead, it is equally probable that the Atlantic would have 

 been bridged by the electric cable at a still earlier date in human 

 history, and that men would have been now gathering harvest from 

 the discovery that is not yet attainable. No one who watched the 

 philosophers of Newton's day, amusing themselves with the pro- 

 duction of the rainbow spectrum from coloured light, could have 

 conceived that the little prism of glass was an instrument capable, 

 in the hands of more modern philosophy and more advanced intel- 

 ligence, of actually sounding the material conditions of the worlds 

 and suns of space, severed from man's theatre of action by such 

 awful voids that the mind of the investigator yet fails altogether to 

 realize the extent of the span through which the investigation is 

 conducted. No one who then looked at the httle prism could have 

 imagined that by it the secrets of the sun's fires were to be revealed 

 — that by it the red flames of the total Solar Eclipse, then only 

 observa1)le during about six minutes at rare intervals, would be 

 turned into objects of daily and continuous study and record, — that 

 by it the proper motion of the remote fixed star, which was rushing 

 directly away from tlie observer, would be detected and measured. 

 Yet all this has now been accomplished by the application of the 

 prism to the Spectroscope, and it is manifest to every thoughtful 

 mind that this wonderful instrument is only yet on the threshold of 

 a mighty career. 



But it should be at once understood that, whilst every point of 

 suggestion and possible investigation should lie eagerly seized and 

 surely tracked, a natural division of the labour is fixed by circum- 

 stance. There are investigations quite sure to be provided for by 

 individual taste and enterprise ; while there are others that neces- 

 sarily require forethought and organization, and that will never be 



