(*21) The Eccalobeion
(*22) Mäelzel’s Automaton Chess-player.
(*23) Babbage’s Calculating Machine.
(*24) Chabert, and since him, a hundred others.
(*25) The Electrotype.
(*26) Wollaston made of platinum for the field of views in a telescope a wire one eighteen-thousandth part of an inch in thickness. It could be seen only by means of the microscope.
(*27) Newton demonstrated that the retina beneath the influence of the violet ray of the spectrum, vibrated 900,000,000 of times in a second.
(*28) Voltaic pile.
(*29) The Electro Telegraph Printing Apparatus.
(*30) The Electro telegraph transmits intelligence instantaneously—at least at so far as regards any distance upon the earth.