30 NATURE AND THE CAMERA 



sary, are useful, for besides showing, as already stated, 

 the local colour and the time of nesting as made known 

 by the presence of the flower, if coloured lantern- 

 slides are to be made the addition of the spot of 

 bright colour, however small it may be, enhances 

 the beauty of the projected picture more than is 

 generally realised. 



For contact prints or even for enlargements the 

 image of the nest should be fairly large, that is to 

 say, it should occupy nearly a third of the plate ; but 

 if for lantern-slide use, it is advisable to show more 

 of the surroundings. So for this reason, when pho- 

 tographing a nest, it is a good plan to make at least 

 two negatives, one showing the nest large and one 

 small. Should the nest be a rare one or a kind dif- 

 ficult to find, make several negatives, giving each 

 one a different exposure. By this method the chance 

 of failure is reduced to a minimum. Nothing is so 

 unsatisfactory as to find, after taking a great deal of 

 trouble in making the pictures, that one has failed 

 through over- or under-exposure, and this is likely 

 to happen to any one, experienced or inexperienced- 

 No one, however many photographs he may have 

 made, can say that he is sure of his exposure under 

 the ever-varying conditions that are to be met in 

 the photographing of natural-history subjects. The 

 question of exposure has been treated in Part II of 

 Chapter I, but all that can ever be written on the 



