THE CONQUEST OF TIME AND SPACE 



and within sixteen hours after starting these had all re- 

 turned to the capital, bearing despatches. During the 

 next few days a score more pigeons were sent out, eigh- 

 teen of which returned safely with their messages; and 

 thereafter a regular pigeon-post was organized. 



As the weight that a pigeon is able to carry in its 

 flight is extremely small, microscopic photography was 

 resorted to, so that, although each bird carried only a 

 single quill in which were rolled thin collodion leaves, 

 the whole weighing only fifteen grains, the amount of 

 printed matter thus carried was sometimes more than 

 is contained in an ordinary volume. 



By photographic methods, thirty-two thousand words, 

 or about half an ordinary volume, were crowded upon a 

 pellicule two inches long by one and one-quarter inches 

 wide, and weighing about three-quarters of a grain! 

 Twenty of these, representing six thousand words, or 

 twice the amount of printed matter contained in such a 

 book as Scott's Ivanhoe, or Prescott's Conquest of 

 Mexico, were carried by each pigeon. One bird carried 

 forty thousand complete messages on a single trip. 



When the bird arrived at its cote, the quill was secured 

 and taken to the government office, where the little 

 leaflets were carefully removed, placed in an enlarging 

 optical apparatus, thrown upon a screen with a magic 

 lantern, and copied. The messages were then dis- 

 tributed to their destination about the city. 



THE DIRIGIBLE BALLOON ACHIEVED 



By this war, France, the home of the balloon, was 

 brought keenly to realize the advantages and the limita- 



[262] 



