164 LIGHT AND COLOURS. [Lesson XXV. 



black cannot with propriety be called a Colour, it 

 being a deprivation of all Light, because the sub- 

 stance stifles all the rays : but white, on the con- 

 trary, is comprehended of all the primary Colours 

 in one, as may be proved experimentally, by tak- 

 ing a small wheel with a broad rim, which let be 

 divided into 360 equal parts; then let 45 of these 

 parts be painted red; 37, orange; 48, yellow; 5O, 

 green; 60, blue; 40, indico ; and 80 of violet ; 

 making in all 360 : if this wheel be whirled 

 swiftly round, the rim will appear as though it were 

 painted of the purest while. It is pretty generally 

 admitted, that the whiteness of the sun's Light is 

 owing to a mixture of all the original Colours in a 

 clue proportion; and hence it is naturally con- 

 cluded, that whiteness in other bodies is a dispo- 

 sition to reflect all the rays of Light in the same 

 proportion and order as they come from the sun. 



My young readers will, I doubt not, after at- 

 tending to what has been advanced in this Lesson, 

 readily unite with me in acknowledging, with 

 gratitiule and joy, the great utility and benefit of 

 Light. For by the help of this admirable, this 

 first-made creature of the Deity ', we are enabled 

 (as before suggested) to behold many other of his 

 glorious works : we can view with admiration 

 and pleasure the beauties of the flowery fields, the 

 gay attire of the feathered tribes, the exquisite and 

 well-adapted proportions of many insects, qua- 

 drupeds, and other creatures; we can dwell with 

 rapture in the coiUemplaiion of extensive land- 

 scapes 



