Contact
Back Next Home

 Various Electrostatic Devices

The thriving curiosity with electricity in the late 1700's to early 1800's resulted in many unique devices, ranging from simple electrostatic generators to unique applications of electricity such as medical machines and perpetual motion. Below are a few examples of these devices:

Electrostatic Bells
18th and 19th Century

Franklin's Bells
During one of his many experiments around the middle of the 18th century, Benjamin Franklin noticed that a pith ball or cork would initially be attracted to a charged object, but if the two touched the ball would be repelled.  He realized that this was because the two objects were initially charged differently (dissimilar charges attract) but once they touched they took on the same charge (similar charges repel).

Franklin realized that if he replaced the charged object with a bell, he could make an "electric bell."  He soon found practical use for his bell as a lightning detector.  When connected it to his lightning rod, the bell would ring whenever an electrical storm was nearby.

Apparently he forgot to disconnect the bells during one of his many trips to France and his wife was quite unhappy with him!

 

Electrical Orrery 1850 - 1860

Representations of the sun, earth and moon in painted wood and bone. All three are balanced on two brass wires and rotate when exposed to static electricity from static generator. This electro-static philosophical accessory is pictured in Benjamin Pike's 1848 Catalog Vol I. fig 316, pg 282; also pictured and described in numerous Natural Philosophy books and other trade catalogs of the period; pictured and described in the King George III Collection as well. American made

 


Hand-held Sparkling Tube
Likely French
mid 19th century

 


Electrical Aurora Tube
Likely American
1840's

Used to create spark and light effect with electro-static generator.


Scintillating Glass Globe
Italian
1820's

With a silver dotted foil spiral conductor which carries electrostatic sparks continuously down the spiral in a dazzling display.

 

 


Scintillating Spiral Tube
English
1850's


Sprial Tube
American
1850


Spiral Tube Array
1870

Popular electrostatic accessories where a dramatic electric display would be created if a static charge were applied to the brass ball finial atop the hand-blown glass tube, the charge would spiral down the path of tin foil disks leading down the tube(s).

 


 Dancing Images - 1840's
 

From the objects in the collection constructed by J.M. Wightman. See pg 216 of Select Experiments in Natural Philosophy by Joseph M. Wightman and illustrated in his 1842 and 1858 trade catalogs as well. Made of walnut and has an adjustable metallic plate. Images of pith or paper figures are put between the plates, and the top plate is connected to the conductor of an electrostatic machine; the images will then begin to "dance" around. Missing top plate. American

 

Dancing Figures Apparatus - 1st Qtr, 19th Century


Little figures of pith or paper are meant to be cut out and laid on the lower brass plate; the top brass terminal is connected to an electrostatic machine and the pith/paper figures begin to dance and jump as they carry the charge back and forth between the plates.  French, 1st quarter of the Nineteenth Century.


Volta "Multi-Pistol"

Six Volta cannons arranged on a spinning disk. The cannons fire in sequence as each cannon's electrode touches the static machine.


Volta Cannon


Air Cannon
c. 1900

 

Very Early Voltas Cannister - 1820's


The elegant flask shape is 5" at it's highest point. Provenance, design, and detailing of brass suggest that this objects dates from the first quarter of the Nineteenth Century and was very likely contemporary with Allessandro Volta. Italian, Very fine condition. Circa 1820's

Electrostatic Weapons?
In 1777 Allesandro Volta was interested in the characteristics of swamp gases.  In order to test flammability he invented his cannon (see below). He would collect swamp gas then fill his pistol with it. The cork on top would be put in after the pistol was filled, to keep the gas from escaping. There would be a metal rod tipped with a brass ball in the cork at the bottom which would serve as a spark plug.

If the gas were flammable, and the proportions right, it would explode when sparked. Volta's early pistols were capable of sending a lead ball twenty feet, and denting a board.18

Long after its scientific use had gone, the Volta Pistol remained a favorite lecture-hall demonstration.

These devices was hardly practical as weapons and certainly not nearly as effective as gunpowder weapons which were common at the time. 


Volta Cannon
C. 1860
Angelo Arrighini
Italy


Volta Pistol


Early Volta Cannon
1787


Inscribed cannon base
"Pistola du Volta 1787"

Group of Volta Canisters - Late 19th Century

From right to left: 1 Volta Canister with Bullseye made of polychromed andvariously painted tin, cork glass and brass; measures 7-1/2" high and bullseye circle is 3-1/2" diameter; 2) Volta's Canister made of above materials, measures 4-1/4" in height; 3) Philosophical Instrument made of same painted tin and multi-colored striped barrel which fits into the main tin container. Unknown what this device was used to demonstrate but likely hydrostatics; measures 7-1/2" in height.  French or German, late 19th century.

 

Electrical Egg Stand - 1840

Consists of wooden frame and three wooden stands to hold as many eggs. A wire and brass ball pass through the upper part of the frame so as to touch the top egg. A piece of metal lays on the bottom of the frame, touching the bottom egg. As an electrical shock is passed on the upper brass ball, the eggs will become beautifully luminous. Apparatus is made of mahogany, whose base is 5" x 3" and is 7-5/8" in height. Described and illustrated in Pike's Catalog Vol. I page 293, figure 340. Fine condition. Likely English circa 1840.

Electrical Sportsmen - Last Qtr, 18th Century
Three figures (left to right) made of hand painted tin with lead weights in base measuring 5-1/4", 5-1/4" and 6-3/8" high. They are beautifully painted, noting considerable loss of original paint. See pg. 283, fig 318 of Pike's Catalog Vol I. French; likely last quarter of the 18th Century.

 

 

Box Containing Electrostatic Philosophical Apparatus - 1st Qtr, 19th Century
Includes: 1) Thunder House made of mahogany, brass, cork and glass. Measures 7-3/8" x 4-3/8 at base and wooden house is 9-1/4" high including brass ball at top of house; glass pillar is 6-3/4" high. Same apparatus as described and illustrated in Public and Private Science: The King George III Collection on page 515, figure E202 and in Benjamin Pike's Catalog Vol. I page 309, figure 369 2) Electrical Bells made of brass. Measures 9" in width from one outer bell to the other. See page 272-273, figure 296 in Pike's Catalog. When exposed to the static electricity of an electrostatic generator these bells give a continuous sublime chime. 3) Set of three Leyden Jars measuring 6", 6" and 6-1/2" high; see pg 260, fig 276 Pike's Catalog; 4) Electrical Pail made of tin, 2-3/8" diameter at top. See pg. 285, fig. 322 Pike's Catalog; 5) Electrical Flyer measures 8" diameter. Made of brass. See Pike's Catalog pg. 280, fig. 313. All the above are in fine condition and contained in a green painted wooden box (in various compartments) measuring 12-14/" x 10-1/4" x 93/4" English, first quarter 19th Century.

 

Cylinder for Dancing Pith Balls - 1840
 

Made of mahogany, boxwood, brass, metal foil and glass. When the prime conductor is connected to an electrical charge, the pith balls placed in the cylinder will dance up and down carrying the electricity from the upper to the lower plate. Mahogany base measures 3" in diameter and the apparatus is 8-7/8" at highest point. See Pike's Catalog Vol. I pg. 277, fig. 303 Fine condition. English, Circa 1840.

 


Electrostatic Induction Apparatus
French
1830's

Glass-legged Stool - 1884


 

Used in early electrical experiments and electro-therapy to insulate the subject from a path to electrical ground.

 

Pair of Insulating Stools - 1st Qtr 19th Century


Made of wood and varnished glass legs. They measure 13-3/4" x 12-1/4" (height: 5-3/4") and 12-3/4" x 9-1/2" (height: 4-1/2") respectively. See pg. 260, fig. 275 in Pike's Catalog Vol. I and pg. 522, fig E216 in Public and Private Science: The King George III Collection Fine condition. English First Quarter of the 19th Century.

 

 


Kelvin Water Electrostatic Machine
4th Qtr 19th Century

Kelvin's Thunderstorm
In 1867 Lord Kelvin -  William Thomson (1824-1907) demonstrated that static electricity could be produced from dripping water.

His experiment consisted of a metal tank filled with distilled water suspended above a table.  The bottom of the tank contained two drains with taps to control the flow of the dripping water. Below each tap was a metal can that collected the water.  A  copper loop was placed just below each tap, between the tap and the can,  so that water dripped from the tap through the loop and into the can below. The loops and cans were cross-connected with a wire (i.e. the loop under the the tap on the right was connected to the can under the tap on the left, and visa versa.)

As the water drops through the air towards the collection can, it obtains a small static charge through induction. Over a period of time the charges build up in the Leyden jars until a spark occurs at the gap. For a detailed explanation of Kelvin's Thunderstorm, see the following page: http://www.amasci.com/emotor/kelvin.html
 


"Thunder Facade"
4th quarter 18th century

The Thunder House
In the late 1770's there was a heated debate regarding the relative merits of a point or ball as the upper termination of the lightning rod. Benjamin Franklin (the inventor of the lightning rod) supported the idea that the rod should terminate in a point; his experiments had shown that a pointed conductor connected to ground would "bleed off" an electrostatic field without the occurrence of a spark. Others (primarily in England where Franklin wasn't well liked due to his support of the American independence) believed a ball would make a better spark gap, after all, most of the devices up to this time used a brass ball as an electrode  - Franklin's "point" being a relatively new idea.

It is reported that Dr. James Lind of Edinburgh invented the Thunder House in order to verify Franklin's theory. Experiments with the device would indicate the Franklin was wrong and the ball is better, but In truth the apparatus proves nothing.  On the enormous scale of  nature there is little difference between the two.

 

The Electrophorus
Invented by Alessandro Volta in 1775, the electrophorus is a simple device for generating static electricity. The glass rod is held in one hand while the metal disk is rubbed with animal fur. An electrostatic charge builds up on the disk which can then be transferred to a Leyden jar, etc.

 

Planetarium  - Early 19th century
At the beginning of the 19th century, there were some who believed the moon’s orbit of the earth was due to static electricity.  This planetarium was designed by an Italian inventor to “prove” the theory. When the device is attached to a friction machine, the gold ball circles the planetarium.

 



Electrostatic Sphere
Italian
Late 19th Century


Electrostatic Pendulum

Operates on the same principle as "Franklin's Bells."


 

Aepinus Condenser - 1880

This is an early device used to experiment with the properties of a condenser (now known as a capacitor.) The Aepinus condenser was the first condenser developed after the Leyden jar and was used to demonstrate conductive and inductive electricity. The device is constructed so that the space between the plates can be adjusted and the glass dielectric (insulating plate between them) can be removed or replaced with other materials.

 
 
Dischargers

Dischargers were used with early friction electrostatic machines to transfer electricity from the machine to another device such as a Leyden jar.


Henley's Universal Discharger


Large Discharger
1860


Upright Discharger
1880


Large Induction Dischargers
c. 1900


Illustration of discharger in use from 1860 book


Glass-handle Dischargers
1884

Luminous Frame
Phrases, and pictures were constructed on the surface of the glass plate using lead foil. When voltage was applied from a static machine, the words and pictures seemed to be displayed in sparks.

 


Riess Distributing Apparatus
1885


Phillip Harris Company
Insulated Conductor
1885


 

Riess Distributing Apparatus and Harris Insulated Conductor - 1885
These devices were used in early experiments with electric fields produced by high voltage friction electrostatic machines.  They were used to demonstrate distribution of charges across the surface of an object as well as induction  - where the charge on one object creates a charge on another object.

 


Field Demonstration Apparatus
1900

 

 

Max Kohl Field Demonstration Apparatus - 1900
This apparatus was used to demonstrate distribution of electric fields on a surface.  It consists of a metal screen with paper strips attached to the surface of the screen (the strips are missing on this unit.) The screen may be manipulated using two insulated handles. As the screen is brought together into a closed loop, the paper strips on the outside surface stand out, while the inside strips do nothing - demonstrating that charge is carried on the outside of a closed surface.


Early Lightning Rod
(Italian)


Lightning Rod
(US)


 

Lightning Rods
Invented by Benjamin Franklin, lightning rods were very popular in the 18th and 19th centuries throughout the US and Europe.  See Thunder House, above, for more information on lightning rods.

 

 

 

Contact
Back Next Home