It was evident that these alfarene nuts were treasure-houses of oxygen; and soon they were tried by the Limanorans themselves when they flew into the upper regions of the air. At first they broke the nuts into powder, which was made into a hard but soluble paste: a small piece of this held in the mouth till it melted enabled them in their flights to breathe freely in rarer altitudes than they had ever reached before. The Floramo afterwards brought out the oxygen-storing power of the shrub more strongly by careful cultivation and selection. Within a few years they made of it a vigorous, large, and comparatively handsome tree, and its nuts grew larger and more oxygenated, so that they became a necessity for all flight into higher atmospheres. More attention was also paid to the floronal or tree of life and to the germabell or tree whose fruit produced elasticity of the muscles and cartilage. The development of all three in the direction in which they might be useful to the race quickened; the energy stored up in their fruits came to be more and more concentrated; selection of the plants, cross-fertilisation of them, special soil and feed for their roots, and special surroundings, were all-powerful in the hands of the Floramo for changing plants and trees to any purpose they had in view. They studied the tissues and habits of the species that they wished to adapt, not as an abstract and merely scientific investigation, but as one of the practical problems of their own life; they turned the clirolan on its inner and outer tissues, as they anatomised it; they watched its inner processes with the lavolan as it grew or decayed; they chemically analysed its sap in all its stages, and the various soils at its roots; then they experimented with new elements in the soil in the direction of the qualities they wished to encourage; they tried it with various degrees and hours of sunshine by day, and various amounts of moisture by night, at different stages in its growth; if they found some of the qualities that they desired in its fruit or tissues more vigorous in some other species, they fertilised its blossom with the pollen of this second plant, and from the seed raised a new species, which would fully realise their purpose. The whole of vegetal nature was plastic in their hands. And every year saw hundreds of new species.