Colomb moved on to tactics. Having first determined by experiment—for which he was given special facilities by the admiralty—what are the manoeuvring powers of ships propelled by steam under varying conditions of speed and helm, he proceeded to devise a system of tactics based on these data. In the sequel he prepared a new evolutionary signal-book, which was adopted by the Royal Navy, and still remains in substance the foundation of the existing system of tactical evolutions at sea. The same series of experimental studies led him to conclusions concerning the chief causes of collisions at sea; and these conclusions, though stoutly combated in many quarters at the outset, have since been generally accepted, and were ultimately embodied in the international code of regulations adopted by the leading maritime nations on the recommendation of a conference at Washington in 1889.