5+ o THE POPULAR SCIENCE MONTHLY. 



new environment, so the philosopher has advanced, step hy step, until 

 he seems almost to have grasped the ultimate particles which constitute 

 the physical hasis of the universe, and to have rendered visible to mor- 

 tal unaided eyes particles of matter which are not only invisible by the 

 aid of the most powerful microscope, but are too infinitesimal even for 

 the mind's eye to conceive. 



"When that marvelous little instrument called the spectroscope was 

 devised, it seemed that man had invaded fairy-land and stolen " a trap 

 to catch a sunbeam," for such it is, in very truth: not only does it catch 

 the dancing sheaf of light, but spreads it out into a band of exquisite 

 colors and exhibits to our fascinated gaze Nature's palette of purest 

 tints, out of which is woven the whole fabric of the gorgeous sunset, the 

 variegated flowers, the bright plumage of the birds, the iridescence of 

 mother-of-pearl, the sparkle and hue of gems, and, indeed, every va- 

 riety of color in nature or in art. 



But this little instrument is still more wonderful, for it combines 

 with its qualities of a trap the advantages of a balance which we may 

 suppose is fine enough for the most fastidious fairy to weigh the nec- 

 tar distilled in the dew-drop, or other delicacy of the season. 



Our ideas of weight and size are purely relative, and that which 

 seems a small or light object, from one point of view, may become 

 large and heavy by a different comparison. To most of us, perhaps, 

 a " grain-weight " suggests a little thing ; we know that the apothe- 

 cary and a few other small dealers split up the grain into halves, quar- 

 ters, tenths, and perhaps even hundredths, but then we regard them 

 as homoeopathic visionaries and laugh at their absurd little pellets ; yet, 

 strange to say, there is a vanishing-point in our minds, which, if an 

 object is small, enough to pass, it becomes larger and more important 

 by reason of our astonishment and wonder at its minuteness : the most 

 ordinary specimen under the microscope is an evidence of this, but when 

 we realize that the ability of the spectroscope to reveal small particles 

 of matter begins where the finest microscope searches with its highest 

 power in vain, that the grain of matter may be divided, not merely into 

 hundredths, or thousandths, or tens of thousandths, but into millionths 

 and tens of millionths, and that a single one of these particles may be 

 readily detected by this little searcher and held up for our inspection, 

 our Avonder and amazement enhance our respect for its occult powers. 

 The astronomer tells us that a comet often throws out a tail longer 

 than the distance between the earth and the sun, and broad in propor- 

 tion; yet the matter forming this tail is so attenuated that, if properly 

 compressed, a gentleman's portmanteau, possibly his snuff-box, might 

 take it in.* Yet we have merely to point this little tell-tale at the 

 comet, and, presto ! we know what the matter is. Think of it ! Not 

 merely can we grasp infinitesimal particles at our hand, but we may 

 sweep the firmament, gather up the star-dust and tell its composition. 



* Sec "Fragments of Science," Tyndall, p. 444. 



