[23] Since writing this chapter I have seen a paper by Luigi d'Auria dealing mathematically with 'Stellar Motion, etc.,' and am pleased to see that, from quite different considerations, he has found it necessary to place the solar system at a distance from the centre not very much more remote than the position I have given it. He says: 'We have good reasons to suppose that the solar system is rather near the centre of the Milky Way, and as this centre would, according to our hypothesis, coincide with the centre of the Universe, the distance of 159 light years assumed is not too great, nor can it be very much smaller.'—Journal of the Franklin Institute, March 1903.
WORKS BY THE SAME AUTHOR.
Travels on the Amazon and Rio-Negro.
Palm-trees of the Amazon, and their Uses (out of print).
The Malay Archipelago.
Natural Selection and Tropical Nature.
The Geographical Distribution of Animals. 2 vols.
Island Life, or Insular Faunas and Floras.
Darwinism.