The lecturer's research on the properties of Electric Waves was begun just twenty-one years ago. In this he was greatly encouraged by the appreciation shown by the Royal Society, which not only published his researches, but also offered a Parliamentary grant for the continuance of his work. The greatest difficulty lay in the construction of a receiver to detect invisible ether disturbances. For this a most laborious investigation had to be undertaken to find the action of electric radiation on all kinds of matter. As a result of this long and very patient work a new type of receiver was invented, so perfect in its action that the _Electrician_ suggested its use in ships and electro-magnetic high houses for the communication and transmission of danger signals at sea through space. This was in 1895, several years in advance of the present wireless system. Practical application of the result of Dr. Bose's investigations appear so important that Great Britain and the United States granted him patents for his invention of a certain crystal receiver which proved to be the most sensitive detector of wireless signals. UNIVERSAL SENSITIVENESS OF MATTER In the course of his investigations Dr. Bose found that the uncertainty of the early type of his receiver was brought on by fatigue, and that the curve of fatigue of his instrument closely resembled the fatigue curve of animal muscle. He was soon able to remove the 'tiredness' of his receiver by application of suitable stimulants; application of certain poisons, on the other hand, permanently abolished its sensitiveness. Dr. Bose was thus amazed at the discovery that inorganic matter was anything but inert, but that its particles were a thrill under the action of multitudinous forces that were playing on it. The lecturer was at this time constrained to choose whether to go on with the practical applications of his work, the success of which appeared to be assured, or to throw himself into a vortex of conflict for the establishment of some truth the glimmerings of which he was then but dimly beginning to perceive. It is very curious that the human mind is sometimes so constituted that it rejects lines of least resistance in favour of the more difficult path. Dr. Bose chose the more difficult path, and entered into a phase of activity which was to test all his strength. CASTE IN SCIENCE