and also passing through the coils, K, will bring down the lever, F, F, and with it, the printer, D, which, as heretofore described, in figures 53 and 54, will bring the type, with considerable force, against the paper. The instant the two pins have come in contact with the moving pin, it is taken out and put in the hole, O, when the same operation is performed, and in like manner for the remaining letters of the word. The pin can be so arranged, as to be thrown out the instant a complete contact is made. The rapidity of this printing process would be as follows: Suppose the pendulum makes two vibrations in a second; that is, it goes from right to left in half a second, and returns in half a second. Since, then, a single letter is brought to the _vertical position_, ready to be used if needed, at the end of each vibration, it is clear, that two letters are brought to the vertical position every second, or 120, every minute. This is not, however, the actual rate of printing; for, in the word _Boston_, the type wheel, after B is printed upon the paper, must make so much of a revolution as will bring the letter O to the paper. This will require 12 vibrations of the pendulum; S will require 4; T, 1; O, 18, and N, 22; equal to 57, to which add 6, the time required to print each letter, will make it 63. This, divided by 2, gives 31½ seconds, the time necessary to print 6 letters. If we now take an ordinary sentence, and estimate, in the same manner, the time required to print it at the distant station, we shall be able to find what number of letters it can print per minute. “There will be a declaration of war in a few days, by this government, against the United States. Orders have just been received to have all the public archives removed to Jalapa, which is sixty miles in the interior, for safe keeping.” Here are 184 letters, and would require 2266 vibrations, to which add 184, the number of letters would give 2450 half seconds, equal to 1225 seconds, the time required for printing the message; or over 20 minutes; the rate being six and two-thirds seconds for each letter. If, however, a vocabulary is used, with the words numbered, and instead of using the 26 letters of the alphabet on the type wheel, we substitute the 10 numerals, in their place, we reduce the time required for a revolution of the wheel, and it is clear that this same message may be transmitted in much less time.