It was decided to get a large quantity of ice and pack it round the explosive in order to keep it as cold as possible. So with this terrible load on their minds the experts left for Liverpool, and returned to find that they had done the right thing. They had kept down the temperature sufficiently to ensure the safety of the nitro-glycerine. With the aid of kieselguhr--an infusorial earth of a very porous character and the inert ingredient of dynamite, and considered by Mr. Alfred Nobel the best vehicle to use as an absorbent of nitro-glycerine--the experts caused the nitro-glycerine to be made into dynamite. It was conveyed to an isolated site near Birmingham, spread out on a tract of land, burnt, and so got rid of. The occupier of the "stationer's" shop and others were subsequently convicted and sentenced to penal servitude for life. October of 1883 brought about two explosions--both on the Metropolitan Railway. The first of these occurred between Charing Cross and Westminster, fortunately resulting in no personal or serious structural injury. That, however, on the same night at Praed Street resulted in three carriages being practically smashed, whilst sixty-two persons were injured by the broken glass and _débris_. An important discovery was made on the 16th January, 1884, of some slabs of Atlas Powder of American make in Primrose Hill Tunnel, and it is surmised that these were thrown away by a conspirator as being of no use for the moment, seeing that it is probable that everything was cut and dried for the somewhat alarming events which occurred in the following month--a quartette of attempted outrages at four London stations, one of which was tolerably successful. On the 26th February, 1884, an explosion occurred in the cloak-room of the London, Brighton, and South Coast Railway at Victoria Station (Fig. 12); whilst on the 27th February, 28th February, and 1st March, discoveries of bags containing Atlas Powder, with clockwork and detonators, were made at Charing Cross, Paddington, and Ludgate Hill stations respectively. In all these cases the clock was used--and that here reproduced is the one found at Paddington--which was left in various cloak-rooms in a portmanteau. The authorities were for the moment at a loss to discover how the explosion occurred, until the police communicated the fact that a portmanteau had been seized at Charing Cross Station. [Illustration: FIG. 12.--EXPLOSION IN CLOAK ROOM AT VICTORIA STATION.] The following extract from the official report will be read with interest, seeing that it also describes how an infernal machine of the clockwork pattern works:--