Would like help with these bulbs

[damato]

I bought a box of about 110 old bulbs and have no idea what I have. I have some pictures and please let me know what I can do to help ID these. The marking on one bulb looks like a O with a line through it. One has Champion in side a diamond and street and railway written outside the diamond. I can only get one picture, what am I doing wrong? Thank You

[Chris Kocsis]

Hi, it appears you have a number of common carbon filament bulbs.  The tip on top indicates probable manufacture before about 1922.  There were many, many different brands.  Off the top of my head, I'm not familiar with one with an O with a line through it for a logo -- but that might be an alignment mark for a test bulb of some sort, such as a brightness standard, which would be interesting.  Is the line perfectly horizontal or vertical, through the center of the O or circle?  You might try posting a picture of that bulb alone.  Note below the attachment box that it says maximum size is 196 KB, perhaps that's a limit on total attachments per post, not maximum for each of 6 permitted pictures per post.

The sorts of bulbs that will elicit replies will have unusual filaments or bases or other features that are uncommon -- and you will have to become a little more familiar with what is common.  Reading the FAQ will help a little bit there, as will exploring the bulb gallery photos.  Maybe you will see similar bulbs to the ones you have.

The one marked railway is precisely that.  See if it has a voltage marking -- it is probably a lower voltage than 110.  By the way, it is not a good idea to light old bulbs unless you are sure of the correct voltage; even a few volts too many will greatly shorten the life.  But if you do have a great number of common ones and you can supply the correct voltage, you might enjoy burning some in accent lamps where their warm glow can be very attractive.  Generally common ones are not worth much, perhaps up to $10.   

I hope this is a little helpful and will encourage you to do some exploring and reading!

[damato]

[img]This is a picture of the bulb with the O and line through it. As the picture shows, there is another make on the opposite side. This line is off set enough so it can be seen without blockage. The bottom og the socket is red and socket looks to be made of steel.  Above the base is written Looks like ETH No. 3498. Inside the bulb on the glass filiment is written 4809 and a little higher is written 4AO85. This is the best I can make them out. They are clear, just have trouble with my eyes seeing it. Thank you

[Chris Kocsis]

Those are definitely alignment markings and would have been used to orient the bulb precisely, but I don't know what for.  Hopefully someone else will have an idea.  The markings on the glass stem are probably manufacturer's code for the plant or run.  The ones above the base though are probably related to the use or at least are a serial number.  By the way, this arrangement of the tungsten filament, with a long thin wire strung alternately between spokes at the top and bottom of a tall glass stem, is usually called a squirrel-cage filament.   This lamp, and the first one you posted, an earlier one that has a carbon filament, both contain a vacuum rather than a gas.  Gas-filled lamps in this size (less than 100 watts, probably) began to appear sometime around and after 1917.         

[damato]

Going through some more of the bulbs and came up with these names: Hygrade 10W 120V, Western Electric Sunbeam 30 Watt-115 Volt, Nalco North American 16CP, Naclco 32CP 110-115Volts, This one has part of the label missing but looks like Fostoria 60W 110V, US Tungsten incadescent Lamp Co. 25 Watt- (not a misprint)112 Volt, Edison Mazda. Do you think these are worth anything to a collector? Does the CP on the Nalco stand for candle power? Thank You

[Chris Kocsis]

Yup, candle power.  In my estimation none of the ones you just listed have particular collectible value, especially the Nalco.  But they could all be the beginning of an interesting collection for you!  I suggest you find and read "Lamps for a Brighter America" by John F. Keating.

Oh, just check whether the Western Electric Sunbeam says "Tantalum" on the sticker, or if the spokes that support the filament are tilted upward at the top of the stem and down at the bottom.  If the latter is the case and the filament is intact, don't light it -- AC is bad for it and it's worth upwards of $100.

[James]

The ETH bulb would have been used for calibrating an early bench-type photometer - a device used until around the 1930s to measure the luminous intensity of other lamps.  The markings on the side of the glass are known as Fiducial Marks, and are used to align the bulb precisely in the photometer in a specific direction for which the luminous intensity is known. 

These lamps were mostly made by GE, and then their light output accurately measured by ETH and the markings put on the glass in the direction of measurement.  They were then sold to other laboratories, national test houses etc, where users could calibrate their equipment by installing the lamp in the same position and driving it at the same electrical current.

Red insulation was used on the screw bases to identify them from ordinary lamps.  The screw bases are bright nickel or silver plated to ensure excellent electrical contact, such that the operating current can be accurately set.

Technically this lamp is little different than other types of its era, but it's certainly not common to find one that has been made for calibration purposes!  Calibration lamps are still produced today by several of the key lamp companies, but sell for many hundreds of dollars in view of the extreme efforts put into producing them to higher standards of quality, and the hours of work invested in precisely measuring their characteristics.  One independent supplier is Polaron Lamps in London, who took over the specialty lamp production of Osram-GEC some years ago.  See http://www.coopercontrols.co.uk/components/spec_lamps.htm