198 Original Articles. [April, 



mirrors of our microscopes ! He lacks not the applause of any ; has 

 therefore no necessity to slight the little and court favour with the 

 great. Nor is He limited by time and space ; constrained to turn 

 His thoughts this way to-day or that to-morrow ; to supervise at day- 

 break here, at sunset yonder. We know full well that whilst He rules 

 in Mars or on our globe, and penetrates our inmost thoughts He also 

 sees the lowliest of His creatures, and numbers not alone the days 

 of Man on earth, but also the few fleeting moments of the animalcule's 

 transient existence. No object is too great, nor any too minute to 

 elude His observation ; and all created works present the impress of 

 almighty will, omniscient wisdom, and unbounded goodness ! 



These are amongst the social, moral, and religious lessons taught 

 by Modern Science, which knows no sect and recognizes no political 

 distinctions, but whose right-minded followers seek to elevate their 

 fellow-men without regard to creed or station and to confer the largest 

 sum of happiness on all mankind. 



ON THE APPLICATION OF SPECTEUM-ANALYSIS TO 

 MICROSCOPICAL INVESTIGATIONS, 



AND ESPECIALLY TO THE DETECTION OF BLOOD-STAINS. 



By H. C. Sorby, F.R.S., &c. 



1. Introduction. — 2. Description of the Instrument. — 3. Spectra of Crystalline 

 Salts, and of their Solutions. — 4. Determination of the relative amount of 

 per- and prot-oxide of Iron in Minerals. — 5. Application of Polarized Light 

 with the Spectrum. — 6. Detection of Blood-Stains. — 7. Conclusion. 



1. Introduction. 



Since various substances may appear to have the same colour, and yet 

 act very differently on the spectrum, or, on the contrary, may give the 

 same characteristic spectrum, and yet differ materially in colour, it is 

 in all cases desirable to study them by means of the prism. As is 

 well known, this method has been employed with remarkable success 

 in various branches of science ; but, so far as I am aware, has not 

 hitherto been applied to microscopical inquiries. In order to accom- 

 plish this, I made a number of experiments, and at length contrived 

 an arrangement which, so far, has answered every purpose required of 

 it. I have also discussed the various particulars with my friends the 

 Messrs. Beck, who intend to adapt a similar arrangement to their 

 microscopes, and we cannot perceive how any considerable alteration 

 could be made with advantage, except such as would be required in 

 the case of microscopes of different construction. I shall therefore 

 describe what I have adapted to my own, one of their large binocular 

 instruments. 



