No Words are Powerful Enough To Express The Importance Of Basic Scientific Research To Our Past, Present, And Future. Click here for more information HISTORICAL INSTRUMENTS OF SCIENCE & TECHNOLOGY FOR SALE & FOR PROPS Jim & Rhoda Morris 9 Morningside Rd. Wakefield Ma. 01880 ---call 781 245 2897 To Email Us For Availability and Prices k1ugm@comcast.net For Sale  a symbolic Spectroscope of the type used in Edison's development of the light bulb.  A beautiful Prism Spectroscope of late1800's   Thumbnail at your left shows the reminisce of the base and collimator of Thomas Edison's spectroscope in his laboratory where he  used it  to invent his light bulb and other inventions. Our  photo above is one of the same type and manufacture. and fully operational. This fine spectroscope is a prism type, giving a brilliant spectrum of ample length and sharpness suitable for the use in becoming familiar with the solar spectrum for observing and charting flame spectra, and analyzing gems from their absorption spectra. The collimator and the telescope objectives have an 18 mm aperture and a focal length of about 200 mm. The telescope has focal adjustment and rotates about the prism axis to permit setting on any part of the spectrum. The scale for measuring wavelengths is mounted on a draw tube to permit adjustment to the focus of the telescope. It is a photographic negative having 22 figured divisions each divided to tenths. The two sodium lines are just resolved in this spectroscope. The prism table cover, for protecting the prism and lenses from dust, is  held onto the table with knurled brass thumb screws. The slit is adjusted through a spring linkage to protect the jaws. The spectroscope stand is a black cast iron base with three legs. The prism table is aluminum and brass. The telescope, collimator and back lighted scale tubes are brass gold lacquered . The prism’s back surface is painted black. The overall condition is very good. Cosmetically it has a few paint chips and some spotting of the lacquered brass. The unit is unsigned. the most likely manufacture date is late 1800. Included are a photograph of the instrument and two engravings showing the optics and a typical bench setup.    AST ITEM # 463

 

The light from a  low pressure electric discharge tube running at about 1/300 of an atmosphere of air and a few milliamps of current is shown on the right side of the photo below.
It  has a purple to white color when viewed by the unaided eye.
When viewed thru a spectroscope the light is sorted out  into a rainbow bar code such as shown on the left side of the photo.
The colors range from deep blue through yellow green to dark red.
When air is heated, such as by the passage of electric current, some of the molecules break apart into individual atoms.
Both atoms and the molecules when heated hot enough will give off light with their own unique bar code of colors.
Since air is a mixture of  molecules of , nitrogen, oxygen with traces of carbon dioxide, water vapor, methane and the rare gases argon thru xenon the  spectrum is quite a complicated set of colored bar codes.
The light from lightning, electric sparks, the  northern lights and during the growth of the fireball of atomic and hydrogen bombs give is  not grossly different than the spectra shown below.
Studying the spectra in the laboratory using spectroscopes has given the Scientist and  engineer an understanding and some times control of the processes which affect the protection of our power grid, radio communication, and the design of weapons of mass destruction, metallurgy, forensic analysis
Last but not least spectroscopes and spectroscopy for the most part is the basic  tool with which we have developed understanding our world and universe.

On the right are pictures of the spectra and Scale  viewed through this spectroscope for Hydrogen, Water vapor, Nitrogen, Air and Mercury. The Graph in the lower center is used to convert the scale readings to wavelength.

Detailed photos of the various parts of a spectroscope.

Prism Table.	Telescope Adjustment	Eye Piece	Slit  Adjustment
Wavelength Scale.	Base	Relative size	.Back to Home page

A laboratory set up to study the chemical, electrical, and optical properties of  gases

The spectroscope is one of the most powerful important inventions  man has yet created. Yet  it has been totally ignored by almost every man and woman in the home the street and the laboratory.   Just think what it represents;  Most every instrument; on the Hubble,  in every observatory, aboard  all of our   planetary probes, chemical labs and factories, crime labs, paint stores, hospitals testing labs, the list goes on and on and on.

They all have and use  spectro-  scopes,  graphs,  meters,  etc. They have been used to measure the chemical composition of our sun, the stars their age their magnetic fields electric fields their velocity ( the expanding universe) the presence of planets around other stars   They have been  used to discover and quantify all of the chemical elements in the period table. For example they told Madam Curie that radium broke down into helium etc   Edison used them to make light bulbs etc.etc   They gave us quantum mechanics They have given us  glimpse of  how our body and brain works They gave us high quality steel sophisticated alloys, plastics, etc.   The list goes on and on and this is just the tip of what they do for us, to us with every breath we take.   Are they important?   You Bet.  and you can have one of your very own.

Return to our main web site

Copyright 1/11/2005 Jim & Rhoda Morris
Permission Granted with acknowledgement when used for academic purposes.