"Of course we know that there is a secret traffic in poisons. Medico-legists, with the police, have established that fact over and over again," said Professor Vega. "But the vendors are very difficult to trace. One was found only six months ago--a doctor living in a suburb of Copenhagen. But orosin is not known to a dozen people beyond those who study toxicology. Hence this man Despujol must have been supplied with it by someone who knew." The suspicion had arisen in my mind that De Gex and his agent Suzor knew that I was in Madrid for the purpose of watching them, and they had resorted to a very clever and secret means of getting rid of me once and for all. If the notorious criminal Despujol was in their pay he would no doubt afterwards blackmail them, now that the desperate plot had failed. Again, could it be possible that Moroni had had any hand in supplying this most effective and dangerous of all secret poisons to the Spanish malefactor who snapped his defiant fingers under the very nose of the police? As I sat in that quiet room of the Professor's, a room that smelt strongly of chemicals, though it was filled mostly with books, I could not refrain from shuddering when I reflected upon the narrow escape I had had. Yet if De Gex resorted to such measures, he must certainly hold me in great fear. Besides, if my life was threatened, so also was that of my friend Harry Hambledon, who remained so vigilant in the serene belief that his presence was undetected. At that time I never dreamed that the great financier who controlled the destinies of certain European States never moved without a police official being in attendance, and that surveillance was kept upon him as though he were royalty travelling incognito. De Gex, it seemed, was ever afraid that one of his enemies, the hundreds whom he had ruined by dint of sharp practice, unscrupulous dealing, and flagrant bribery, might seek revenge. Hence, though neither Hambledon nor myself knew of it, both De Gex and his toady and agent, Gaston Suzor, were well aware of our presence, and, moreover, were kept posted concerning our movements from day to day! Though we were in ignorance of all this, yet the desperate nature of the plot against me caused me to wonder what exactly was the fear in which De Gex held me. Of course it concerned Gabrielle Tennison. But exactly how, I failed to surmise. One thing was certain, that the mystery-man of Europe intended to rid himself of me, and in this he was being aided by certain of his friends, chief among whom were Suzor and Moroni. That the assassin Despujol was only a paid servant was quite clear. But the pay must have been a very handsome sum to cause him to dare to come to Madrid so boldly and run the risk of arrest.