Caselli made a prototype of his system by 1856 and presented it to the Duke of Tuscany (Leopold II), in a demonstration that used telegraph lines. The Duke was so impressed with Caselli's device that for awhile he financed his experiments. When the Duke's enthusiasm waned Caselli moved to Paris to introduce his invention to Napoleon III. Napoleon immediately became an enthusiastic admirer of the technology. Caselli perfected his pantelegraph (also known as the autotelegraph) between 1857 and 1861 in Paris under the leadership of French inventor and engineer Paul-Gustave Froment. The world's first practical operating facsimile machine ("fax") system put into use was by Caselli with a scanning technology he devised. Alexander Graham Bell received his telephone patent in 1876 - that then introduced telephone lines for the first time.