And every star had, in their science, its own peculiar influence, sometimes malign, more commonly beneficial, when treated according to their wise discoveries. Little of all this would have been possible without the inolan or measurer of light, one of the most delicate instruments they possessed. This was but a modification of the human eye as it had been developed in their bodies. It magnified the impression made on the lens so that it should move a small mirror delicately hung _in vacuo_; the reflection of this mirror ran along a graduated scale on which it recorded by bleaching a point of colour, the energy of light in the beam producing the movement. This recorded not merely the strength of the rays of which their eyes were conscious, but that of many octaves of light outside of the range of all human eyes. A more modern and delicate form of the inolan used a microscopic camera as the medium of measurement; this had accomplished new wonders in the way of measuring the power of rays from stars out of reach of the human eye. A third photometer, recently invented and still untested when I visited the collection of measurers, had made use of electricity in collecting and testing the quality and energy of beams of light. In all of these forms of the inolan there was an arrangement for ridding each ray of its heat and of other forms of energy before it entered the lens; a thermometer measured the heat; and the other elements were absorbed and analysed by a subsidiary apparatus as the beam approached the inolan. Another modification of the apparatus had a prismatic arrangement attached to it, not unlike their inamar, and this broke up the beam of light into its colour components; the inolan measured each separate component, the length of its wave, and the energy required to produce it, its camera also recording in photographic form the metallic elements through which the beam had passed. A more recent modification, promising great results, was one which by means of a vacuum-lens recorded the dark beams that shone from unseen stellar bodies through the corona of our own or other suns. When fully developed they expected this to reveal the secrets of the darker depths of the heavens; the systems revolving round the stars would stand out clearly with all their elements for the investigation of the astronomic families. Nor did the extraordinary refinement of these instruments, that were constantly being discovered, interfere in any way with the development of Limanoran senses. On the contrary they stimulated advance. Every new aid to any sense pointed the way to its improvement; and in a few years or generations this aid was rendered almost superfluous and a new and more delicate machine must be invented; for the combination of so many functions in the living body rendered the observations of any one sense less exact and trustworthy than those of a machine which had but one purpose.