There was in Paris, when the siege commenced, a society or club of pigeon-fanciers who were specially interested in the breeding and training of “carrier” or “homing” pigeons. The leaders of this club now came forward and suggested to the authorities that, with the aid of the balloons, their birds might be turned to practical account as letter-carriers. The idea was at once taken up, and henceforward every balloon that sailed out of Paris contained not only letters and despatches, but also a number of properly trained pigeons, which, when liberated, would find their way back to their homes within the walls of the besieged city. When the pigeons had been safely brought out of Paris, and fallen into friendly hands beyond the Prussian forces, there were attached to the tail feathers of each of them goose quills, about two inches long, fastened on by a silken thread or thin wire. Inside these were tiny scraps of photographic film, not much larger than postage stamps, upon which a large number of messages had been photographed by microscopic photography. So skilfully was this done that each scrap of film could contain 2500 messages of twenty words each. A bird might easily carry a dozen of these films, for the weight was always less than one gramme, or 15½ grains. One bird, in fact, arrived in Paris on the 3rd of February carrying eighteen films, containing altogether 40,000 messages. To avoid accidents, several copies of the same film were made, and attached to different birds. When any of the pigeons arrived in Paris their despatches were enlarged and thrown on a screen by a magic-lantern, then copied and sent to those for whom they were intended. This system of balloon and pigeon post went on during the whole siege. Between sixty and seventy balloons left the city, carrying altogether nearly 200 people, and two and a half million letters, weighing in all about ten tons. The greater number of these arrived in safety, while the return journeys, accomplished by the birds, were scarcely less successful. The weather was very unfavourable during most of the time, and cold and fogs prevented many pigeons from making their way back to Paris. Of 360 birds brought safely out of the city by balloon only about 60 returned, but these had carried between them some 100,000 messages. Of the balloons themselves two, each with its luckless aeronaut, were blown out to sea and never heard of more. Two sailed into Germany and were captured by the enemy, three more came down too soon and fell into the hands of the besieging army near Paris, and one did not even get as far as the Prussian lines. Others experienced accidents and rough landings in which their passengers were more or less injured. Moreover, each balloon which sailed by day from the city became at once a mark for the enemy’s fire; so much so that before long it became necessary to make all the ascents by night, under cover of darkness.