Ari Davis (ca. 1811-1855) was a skilled American craftsman who received two patents in 1854. One (#10,788 of April 18) described a machine for producing wooden boxes with metal-reinforced dovetail corners. The other (#11,415 of August 1) described a magneto-electric machine. While this second patent was still in process, Davis sold the rights to both patents to Walter Kidder, a physician in Lowell, Massachusetts, allegedly for $4000. Advertisements for DAVIS’ (later DAVIS & KIDDER’S) PATENT MAGNETO-ELECTRIC MACHINE, FOR NERVOUS DISEASES were soon to be seen. By 1857, the business was in the hands of William H. Burnap (b. 1825), also of Lowell. By 1865, Burnap was working in New York City, and advertising as “Manufacturer of Davis & Kidder’s Electric Machines.”
This example is in a wood box with brass corners. A two spool armature driven by a crank, a large horseshoe magnet field piece and two hollow brass hand grips with cords. Grasping both brass hand grips and cranking magneto would result in a shock voltage designed for therapeutic: purposes. The paper label is marked “DAVIS & KIDDER’S / PATENT MAGNETO-ELECTRIC MACHINE / FOR NERVOUS DISEASES” and “PATENTED AUG. 1, 1854” with testimonials from Silliman (at left) and Paige (at right). The text at bottom reads “Manufactured and sold by W. H. BURNAP, Sole Proprietor, 163 West 27th St., New York, whose signature is attached to all genuine / Machines. All infringements upon his Patent will be prosecuted.”
Telegraph sounders convert electrical pulses into audible sounds and are used to receive Morse code messages. The message travels as a series of electrical pulses through a wire. Short pulses make a dot, slightly longer pulses make a dash. The sequence of dots and dashes represent letters and numbers. The pulses energize the sounder’s electromagnets which move a lever-arm. The arm makes a loud “click” when it strikes a crossbar and the operator translates the pattern of sounds into the original language. This very early sounder, made only a dozen years after Morse's "What Hath God Wrought" message, is ornate and features a marble base plate.
Electromagnet Demonstration Apparatus. Two coils, each 2 3/4" diameter, are affixed to a soft iron horseshoe. This electromagnet in turn is suspended from a hook which can be raised or lowered by a screw mechanism. An iron triangle with a wooden lift pan is mounted beneath the electromagnet for the purpose of demonstrating pulling power. Framework is of wood.
The completion of the first transatlantic telegraph cable in 1858 was a cause for much celebration on both sides of the Atlantic. Tiffany & Company of New York purchased the cable remaining on board the USS Niagara after the successful completion of the cable and sold 4-inch sections as souvenirs. Each section of cable was banded at the ends with brass ferrules and had a brass plaque that read “ATLANTIC TELEGRAPH CABLE/GUARANTEED BY/TIFFANY & CO./ BROADWAY • NEW YORK • 1858.” The cable souvenirs originally sold for 50 cents and came with a reproduced letter of authenticity from Cyrus W. Field, the pioneer of the transatlantic cable system. The jubilation turned to jeers when the cable failed a few weeks later, and Tiffany never sold its supply of cable. In 1974 Lanello Reserves began reselling the transatlantic cable, and donated this object to the Smithsonian.
Telegraph keys are electrical on-off switches used to send messages in Morse code. The message travels as a series of electrical pulses through a wire. The operator pushes the key’s lever down briefly to make a short signal, a dot, or holds the lever down for a moment to make a slightly longer signal, a dash. The sequence of dots and dashes represent letters and numbers. This is a very early strap key used by Joseph Henry in experiments made at the Smithsonian.
Submarine Telegraph Cable. Laid in 1856. Solid iron conductor, No. 7 B.&S. gauge, covered with gutta-percha, without armor, brittle and badly cracked. To the cable is fastened one leaden weight, 2 1/2 inches long, 1 1/2 inches in diam. in the center tapering to the ends, with longitudinal slot in which the cable is placed and the lead hammer to tighten it on the cable. Laid between Nantucket Island and the Massachusetts mainland.