Thank you for visiting my booth at Maker Faire. This page will give you a bit more information regarding the devices on exhibition, as well as some links and notes on how to make your own version of these devices.

On Saturday, October 15th and Sunday, October 16th I will opening my studio to the public between noon and 6pm as a part of the Annual Gowanus Open Studios. My studio is located at 75 10th St., near the Gowanus Lowes on the 2nd Floor in Room 21. Come by and see my shop, and some more of my work.

Electrophorus
The electrophorus is capacitive generator, and produces charge through electrical induction. A rabbits fur or cloth gives up electrons to the insulating plate when it is rubbed onto it. The brass plate is then placed ontop of the insulator, and grounded (this is done by pressing a finger onto the brass plate). When the plate is lifted via the insulating handle, a charge is lifted with it. This charge can then be used in various experiments.

Here is some more detailed information on the function of an electrophorus. And here are some links to instructions for making your own.

Electroscope
The electroscope is an early version of a voltmeter. It is a way of detecting an electrical charge. In the presence of an electrical charge, the two halves of the gold foil become charged the same, and so they repel. Measuring the angle of deflection provides a way of comparing relative charges. This type of electroscope with windows on the front and the back of the device was used in lectures, and allows a light to pass through the instrument, which would cast a shadow, and allow a large audience to view the measurement.

Here is a nice page full of historical instruments. And here are some links to instructions on how to make your own.

Spinthariscope
The Spinthariscope is a device for viewing the decay of alpha particles from a radioactive source. This spinthariscope uses Americium 241 which can be found in most smoke detectors. It is an alpha emitter, and is therefore relatively safe to work with (don't eat it, and wash your hands after handling it). The alpha emissions strike a zinc sulfide screen which causes it to emit a photon. Using a loupe to magnify the surface of the screen allows you to see the faint pulses of light. It is important to allow your eyes to dark adjust for 10 or 15 minutes in order to see these pulses.

A link to the history of the spinthariscope. A diagram of how the device is constructed.

Cloud Chamber
A cloud chamber is a way of seeing the particles emitting from a radioactive source. There are two basic types of cloud chamber a diffusion chamber, or an expansion chamber.

The diffusion chamber is a standby of science fairs and museums. It is reliable, and very easy to make, place black felt in the bottom of a petri-dish, saturate the felt with isoproponol, drop in your radioactive source, and place it onto some dry ice. Here is a video showing how to do this. And here is a link showing how to make one with a fish tank.

An expansion chamber is a bit different rather than use temperature to cause the cloud tracks to form, atmospheric pressure is used. The atmosphere inside the jar is satured with alchohol vapor. When the pressure inside the vessel is decreased, cloud trails will form in the path that the particle is moving though the space. So it works similarly, however it is a more fleeting image. Here is a video describing the construction and operation of an expansion cloud chamber.