Pen and Ink Sketches 47 
most of the nests depicted were in places of which it was impossible 
to get a general view, since they were out of sight of everybody 
save the man on the spot. 
For photographing nests on the ground or in marshes a camera 
stand is often useful. Here again I carry the very lightest possible 
pattern and look to its rigidity of construction to minimize the 
vibration caused at times by the wind. Very seldom is a stand of 
any use in cliff work. In such places one has to be extemporized 
out of some ledge or shelf of rock and the camera placed upon it and, 
if necessary, wedged up in the required positions by small fragments 
of rock. Where no horizontal ledge can be utililized the camera 
must be held rigidly with one side pressed firmly against some 
vertical crag. A large proportion of the photographs given are the 
result of long time-exposures in deep shadow on cliffs and often in 
gloomy caverns and in no case was I ever able to use a stand, but 
had to extemporize one as described. 
In reproducing the photographs for this book, in four cases only 
has it been thought desirable to retouch a negative. The remainder 
are as in their original state. 
The pen and ink sketches are, with some few exceptions, facsimile 
copies of the water-colour drawings made by me on the spot during 
the last thirty-three years. 
