io 4 NATURE NEAR LONDON 



listen better, there could be no doubt of it : it was the 

 tramp of this immense army. 



The majority still moved in one direction, and I found 

 it led to the heap of rubbish over which they swarmed. 

 This heap was exactly what might have been swept 

 together by half-a-dozen men using long gardeners' 

 brooms, and industriously clearing the ground under 

 the firs of the fragments which had fallen from them. 

 It appeared to be entirely composed of small twigs, fir- 

 needles, dead leaves, and similar things. The highest 

 part rose about level with my chest say, between four 

 and five feet the heap was irregularly circular, and not 

 less than three or four yards across, with sides gradually 

 sloping. In the midst stood the sapling birches, their 

 stumps buried in it, the rubbish having been piled up 

 around them. 



This heap was, in fact, the enormous nest or hill of a 

 colony of horse ants. The whole of it had been gathered 

 together, leaf by leaf, and twig by twig, just as I had 

 seen the two insects carrying the little stick, and the 

 third the brown leaf above itself. It really seemed some 

 way round the outer circumference of the nest, and while 

 walking round it was necessary to keep brushing off the 

 ants which dropped on the shoulder from the branches 

 of the birches. For they were everywhere ; every inch 

 of ground, every bough was covered with them. Even 

 standing near it was needful to kick the feet continually 

 against the black stump of a fir which had been felled to 

 jar them off, and this again brought still more, attracted 

 by the vibration of the ground. 



The highest part of the mound was in the shape of a 

 dome, a dome whitened by layers of fir-needles, which 

 was apparently the most recent part and the centre of 

 this year's operations. The mass of the heap, though 



