searched for signals before fixing an ambush. If they saw that flowers are in the window and the person whom they have come to arrest has tried by all means possible to take these flowers away, the police insisted on putting them back in the place where they were. So, when arranging safety signals for reporting places, it is necessary to arrange them in such a way that they don’t strike the eyes of the police and that they can be taken away without being noticed by the police. For verifying those who come to the reporting places, a system of passwords is established. The comrade comes to the reporting place, and he says some agreed-upon sentence. They answer to that agreed-on sentence by some other agreed-on sentence. So both comrades check each other. In Russian underground conditions very complicated passwords were sometimes used in the central appearing places. This was called forth by the circumstances that different workers passed through such reporting places; rank and file workers from the cells, district and Central Party workers. Accordingly, one password was fixed for the rank and file worker, a more complicated one for the district worker and still more complicated one for the central worker. Why was this necessary? It was necessary for conspirative reasons, since only certain things could be said to the rank and file worker while perhaps other things could be said to the district worker, whilst you could speak with full frankness about the whole work of the illegal organization to the representative of the Central Committee. Therefore, passwords were, as they used to say at that time of “three degrees of trust.” This was done in this way. The first degree of trust: a comrade comes and says an agreed-upon sentence and is replied to by an agreed-upon sentence. The second stage: the comrade who has come in reply to the agreed-upon sentence spoken to him, says another agreed-upon sentence, in reply to which yet another agreed-upon sentence is spoken to him. The third stage of trust: to the second agreed-upon sentence the comrade replies by a third agreed-upon sentence. Then the keeper of the appearing place also replies to the third agreed-upon sentence.