WOOD AND WASTE 155 



the side of over-caution. Still, as a rule, 

 the processes of sapping and mining can 

 hardly be too gradual, and in our operations 

 against the Tui it was, after all, rather the 

 weather and the very rapid development of 

 the young that beat us. 



Among all species throughout the rearing 

 of every brood there is a gradual increase 

 of devotion to the nest and offspring, this 

 devotion culminating a few days before the 

 birds are fit to fly. A nest in building will 

 often be deserted if looked at, neither when 

 complete is it of much account in the eyes 

 of the little builders; even eggs, when 

 perfectly fresh, inspire no great ardour. 

 As, however, they approach complete in- 

 cubation, so in exact correspondence do the 

 parental instincts of care and tenderness 

 increase. Then, again, there is a great leap 

 in parent love from the moveless, quiet 

 shells to the pathetic little creatures that 

 move and wriggle in the nest. 



They become daily more and more 

 precious, until the feathers are almost 

 complete, when the old birds' affection begins 

 slighth^ to cool, or perhaps, rather, they 



