152 THE BOOK OF THE LANTERN. 



know very well that the odds against such an occurrence 

 amount to an enormous figure, but no mathematician 

 would be able to calculate the number of different tints 

 that we can procure, even from the three primary colours. 

 We have such tints in the beautiful solar spectrum, 

 but there they blend into one another so gradually that 

 no eye can count them. 



One of the great helps to success is to observe the rule of 

 being very sparing of both colour and medium when dab- 

 bing in the sky portion of the picture ; but the painter can 

 be more lavish with both when he is dealing with foliage, 

 and any broad masses of light or shade.* Here he can 

 often use a large camel-hair brush, and can mop in the 

 colour, only taking care that he does not go over the out- 

 line which circumscribes the particular portion of the 

 picture he is working upon. In the case of a mass of foliage, 

 let him mix up the desired paint on the palette with a 

 flexible palette knife, which he should always have at hand. 

 This should be done thoroughly and quickly ; then let him 

 take up a moderate quantity of this colour in the brush and 

 mop it on to the surface of the picture. For this class of 

 work mastic varnish, very much thinned with turpentine, 

 forms a capital vehicle. The .strength of this mixture may 

 be one part of mastic to six of turpentine. This medium 

 keeps liquid long enough for careful manipulation, and yet 

 it dries quickly in comparison with other media which 

 might be named. 



Photographic transparencies are now produced of such 

 varied tones that in many cases it will be found advisable 

 to leave portions of the picture quite uncoloured. With 



