Daniel Davis Jr. was the first American professional maker of electrical machines. He also wrote several important books on electrical machines and instruments, including the first catalog of commercially available electrical machines made in his workshop.

Daniel Davis Jr. was born in Princeton, Mass, in 1813, during a decade which saw the birth of most of the well-known American apparatus makers of the nineteenth century. In 1833 at the age of twenty he moved to Boston where he worked in a factory which produced chemical soda, and was then employed by William King, who made lightning rods and electrical machines. By 1837 Davis had become known as a skilled instrument  maker and he went into business for himself making electrical machines. He set up a shop with his brother Ari in Boston for the making of electric apparatus.

Horizontal galvanometer by Daniel Davis, Jr.

Daniel Davis Jr. was the first maufacturer of educational apparatus in the United States and possibly the first American to specialize in only making electrical devices. Like his contemporaries, Davis' entry into the field of scientific instruments was as an artisan, rather than as a scientist. He was the first American maker of  mechanical machines that generated constant  electrical current for electrochemical experiments. Davis made instruments for local scientists, one of which was a physician named Dr. Charles Grafton Page. Page was an experimentor and a prolific inventor of electromagnetic devices, many of which Davis produced and sold. Dr. Page invented a battery in 1837 that used released hydrogen to depress the electrolyte. Davis built the battery for Page, although it was never reproduced because of its ineffectiveness. Davis did not list or mention the battery in any of his catalogs. Davis and Page continued their business relation after Page moved in 1838 to Washington, DC. Page even made several trips to Boston after moving to consult with Davis on the construction of electrical devices, but after 1849 began to look for a local instrument maker.

 

Davis published a catalog entitled "Descriptive Catalogue of Apparatus and Experiments, Electro-Dynamics, Magnetism, Electro-Magnetism, Magneto-Electricity, Thermo-Electricity" of his electrical instruments for sale in 1838. Davis listed and described 68 instruments within the 72-paged catalog, and also described electrostatic machines although they were not part of the title. The catalog of 1838 had improvements on 41 of the previously listed instruments. Six instruments in the catalog were accredited to Page by Davis and were: 1) the reciprocating armature engine, 2) an induction coil, 3) a galvanometer, 4) a double helix for inducting magnetism, 5) a revolving armature for displaying motion by magnetism, and 6) a vibrating armature. Davis marketed Page's rocking beam motor for $12.00, and his magnetos from $35.00 to $75.00. Catalogue of Apparatus, by Daniel Davis, Boston, 2nd edition, 1848

 

Primary and Secondary Coil

	This removable winding induced current apparatus was made by Daniel Davis Jr. and dates to 1840 - 1850. This was manufactured for educational purposes and consists of a heavy gauge primary (inner winding) and a finer gauge  removable secondary winding. The base is mahogany and the layers of windings are separated by newspapers. The original binding posts are missing, the plugged holes for these can be seen at the back edge of the coil base. The secondary winding (outer winding) is 10 -12 layers of  about 234 turns/layer of  24  gauge (approximately) wire. The secondary resistance is about 345 ohms. The upper and lower brass caps on this winding are slotted.
	The primary winding (inner winding) is 2 layers of  114 turns/layer of  14  guage (approximately) wire. The primary resistance is about .7 ohms. The primary is wound on a slotted (lengthwise) brass tube.
	"Daniel Davis Jr. Manufacturer. Boston."

 

In 1842, Davis published a manual entitled "Magneto-Electricity, and Thermo-Electricity" which was authored for students of various institutions. He illustrated and described a small magnetoelectrical machine designed in 1837 by Dr. Page that included a device for making and breaking the circuit. Davis had a section that stressed galvanic electricity and its magnetic effects. He also described the electrotype process, electroplating, and some electrolytic experiments in the catalog. One of his machines was described as being useful for electroplating, but it was adopted by educational institutions for scientific demonstrations rather than for commercial use. Electroplating was a new process at the time, and not yet perfected or well understood. Professor Silliman of Yale College and editor of the American Journal of Science praised the manual written by Davis. The manual was used by the United States Military Academy and other institutions as a textbook, and was successful enough to have 13 editions between 1842 and 1872.

 

Davis, in 1846, published a manual "The Medical Application of Electricity", Boston, and a pamphlet "The Medical Application of Electricity with Descriptions of Apparatus and Instructions for its Use in Boston". In the pamphlet he discussed galvanic belts and rings that were made using two different metals that contacted the skin when used. He indicated that the belts produced small amounts of current. Davis did not accept the contention that such metallic devices could pass electricity to various organs of the body as claimed by advertisements of 1846. He even concluded that the galvanic belt (very popular 1880s-1890s) was a device of quackery.

Davis published his second manual in 1852 which was entitled "Manual of Magnetism", but used the same year to retire from instrument making and dissolve his relation with Page. In Page's book History of Induction of 1867 he cited Davis several times for his catalog listings and descriptions.