EVOLUTION OF THE SANS RIVAL KOSMOS CHIMNEY
Wild & Wessel of Berlin (W&W) in 1865 developed the "Kosmos" burner, where a flat wick is formed into a round shape. Wild & Wessel was producing a side-draft burner in 1883 with a flame spreader, a year before the Henkle patent flame spreader was put into production by Charles Upton in his Rochester lamps.
Both side draft and center draft lamps were produced concurrently for years, side draft burners being less expensive to produce because the font did not require the expense of a center draft tube. Indeed, side draft "Kosmos" lamps are still in production, more than half a century after the last Rayo center draft lamp was produced in August, 1955 in Meriden, CT.
Both side draft and center draft lamps employ the flame from fuel burning above a wick to provide light. The size and shape of the flame front determined the light output. In general, center draft lamps used a flame spreader to produce a wide, relatively flat flame. Side draft lamps used flame height to have a sufficient flame front to provide adequate lighting.
Center draft lamps generally had a burner cone which provided a constriction to induce a draft, whereas for a side draft burner that necessary constriction was part of the chimney. And that is the beauty of the Sans Rival chimney - it was designed to encourage the flame to be stable at 2 1/2 to 4" in height by using triple chimney constrictions to increase the draft. The increased draft associated with the Sans Rival chimney induces a cooler burner and font, and that means the flame is more stable, burning for many hours without changing the flame height.
The genesis of the Sans Rival chimney (sometimes referred to as "Phenomen") appears to have been the work of Mr. P. Bayle; his experimental work on chimney combustion principles influenced many subsequent chimney designs as his work was published in the Scientific American Supplement No. 458 on October 11, 1884. (Kindly provided by William Sogge).
Please note there were many types and styles of "Kosmos" lamps, some with true wick carriers, some without. Some used wide flame spreaders and require a bulge style chimney (true Matador) while others used a narrow flame spreader but nevertheless used a unique constriction type chimney, such as the Imperial/Vulcan lamps made by Wild & Wessel. A few rare lamps used a straight chimney. In general, for those Kosmos side draft burners which did not use a flame spreader, the Sans Rival chimney is literally without rival.
The original Sans Rival Chimney was made in Germany. "There were several firms that imported “Sans Rival” chimneys into Norway from Germany: Peter M Kolderup (est 1854) and Johan Tomsen A/S (est 1904) being the best known.
"As for the age, these were catalogued sometime between 1900 - 1930, though production probably ended during WW I. This I can say fairly accurate because of oil lamps I've seen in museums and photos from back in the day where one could see the sans rival chimney fitted to various oil lamps.
"The Thomsen imported chimneys were the most exclusive ones: superb clarity, very heavy being made of thick "cristal" glass and almost never have air bubbles in them."
Information provided by William Sogge
The dimensions of the 14 Line Sans Rival chimney are shown to the left. They are precise copies of the original chimney, but made in thermal shock-resistant borosilicate glass.
Base diameter: 2.031" - 2.05"; 1.905" up to the pinch, which is 1.175". The draft control constriction is 1.039" in diameter. The base of the upper chimney is 1.030" in diameter, tapering out to 1.184" at the top. The overall height is 10 3/4". Both ends are highly polished so they will not chip.
The two extra constrictions in the chimney draw the flame up to form a tall, beautiful "Christmas Tree" effect (below) in brilliant white light, unlike any other Kosmos chimney.
The Sans Rival's enhanced draft and flame control allows for the brightest white light on any 14''' Kosmos lamp. And that wonderful draft control means that even at a very low 
setting, for example as a night light, the lamp produced clean, odor free burning. So clean, in fact, that the chimney seems to stay clean and without a trace of smudge even after many days of burning.
I purchased a pretty poor example of a 14''' Kosmos lamp almost 20 years ago. There was a pinhole leak in the glass font. Fixed that with radiator epoxy. I fired it up and it smelled horrible. It traveled to a shelf in a storage room and stayed there for all this time. A few daysago I dug it out, straightened the collar so the chimney would be fairly close to vertical, installed a new wick and tried it again. Still smell horrible from a too-rich mixture not be able to fully burn in a conventional Kosmos chimney. I stuck on a Sans Rival chimney and it burns white with absolutely no aroma. The Sans Rival chimney burns hot and the secondary combustion chamber burns up all residual vaporized fuel so there is no aroma when burning the lamp!
By far the most common size Kosmos-style lamp is the 14'''. They were produced in many countries in Europe for over a century. It is therefore no surprise that chimney base diameters varied considerably for what was listed as standard 14''' lamps. The Sans Rival chimney has a base diameter of 2.031". I have other 14''' chimneys which range from 2.00" to 2.109" diameter - about the maximum diameter which will fit the burner. All chimneys get hot in use, and glass expands when hot. There should be spring finger tension to hold the chimney in place so when hot the chimney has room to expand.
Never used your fingers to bend chimney prongs - it is far too easy to bend the fingers too far and break them, plus the individual fingers will not be adjusted evenly. If a chimney fits too tightly, gently bend the fingers out from the inside by using the convex side of a teaspoon. To bend chimney fingers in, something about the diameter of an AAA battery can be held horizontally right in the curl of the chimney fingers and moved around the outside of the fingers, gently bending them in to have a uniform spring tension. Start the bending process at the wick raiser knob and end there for uniform concentricity.
Below is a photo of the hunting cabin in northern Norway where William Sogge found the original Sans Rival Chimney. And there is the 14''' Kosmos lamp burning brightly in the same place it has hung for a hundred years.
And here is the signed original Sans Rival which was used to make the mold for my Sans Rival chimneys
Testing and Trials.
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| Test A: |
Test B: |
Standard modern 14-line chimney on same lamp. One I consider typical of today's Kosmos chimneys (poor constriction shape). Chimney was about 1/2 inch shorter overall than the San Rival. Turned up until it smoked and then turned back until it burned clean.
TEST A.
San Rival Chimney, burner turned up until it started to smoke and nudged back to a clean burn.
Light level at 21" away with flat field light meter attachment and angled to get maximum illumination reading = Exposure Value
(EV) 3.75 @ 100 ASA/ISO (36 Lux)
TEST B.
Light level at 21" with same meter arrangement and angled for maximum illumination reading = Exposure Value (EV) 2.88 @
100 ASA/ISO (27.6 Lux)
EV levels are logarithmic, thus a change of ± 1 EV is twice or half as much light. So, the San Rival put out 3.75 - 2.88 = 0.87 EV more light = 1.8X as much light as the standard chimney was capable of. So almost twice!
Disclaimer - none of this was precise science! I just tried to equalize the conditions and photographic angle for the comparisons.
Peter Brickell, Toronto August 15, 2011