35 



of its minute structure, would seem probable to every naturalist ; and 

 the Society would be prepared to look with favour upon an explana- 

 tion which referred it to the composition of two combining or opposing 

 forces, as in Mechanics and Electricity, even though the way should 

 not seem clear for pointing out the exact nature of the forces them- 

 selves. Such an explanation he had to submit. It would account for 

 every peculiarity in the form of branches and leaves, considered as 

 such, but it was so entirely independent of the well-known laws which 

 regulated the formation of wood rings, &c, that it seemed impossible 

 at present to harmonise the two. If his position were true, they would 

 ultimately be harmonised. If false, the facts at least were worthy of 

 notice ; in any case he claimed for his scheme the consideration due 

 to lengthened investigations under very favourable circumstances. 

 For fifteen years he had bestowed pretty constant attention to this 

 subject. He had made some hundreds of measurements in England, 

 Australia, and Peru, on trees of all sizes, from the lilac and alder to the 

 Eucalypti. For this purpose, he had used, successively, a lad>^s 

 measuring tape, a sur^-eyor's chain, and a theodolite or sextant, 

 and on one occasion had allowed himself to be hoisted 120 feet in the 

 air by a rope drawn over with the help of a bow and aiTO\v, but never 

 had he found a single instance of departure from the principles 

 described. 



It was not at every period of a tree's life that it possessed a 

 perfect form. During what might be called its childhood the branches 

 were not yet visible ; in its advanced maturity the true branches were 

 intermixed with subsidiary limbs, forming no part of the original plan, 

 and produced by the development of what would have been mere 

 twigs but for accidents to which he should hereafter refer ; while old 

 age showed us a confused and tangled mass of branches, broken and 

 repaired, or bent in distorted forms to avoid collision with others, or to 

 take advantage of some accidental condition. But there was a 

 time in a tree's historj- which might be likened to our own useful 

 prime, when the graceful structure presented neither the bareness of 

 the sapling nor the unintelligible luxuriance of the maturer growth, 

 and when the laws to which he had referred might be easily recognised 

 and fully traced. He had spoken of branches as normal and subsidiary 

 or accidental, and it was necessary that he should justify such a 

 distinction . By way of doing so, he would ask those who had seen 

 trees cut or split longitudinally to try and recall the appearance of the 



