0
REMARKS ON THE HISTORY OF LABORATORY BURNERS' MORITZ KOHN New York City (Translated by Ralph E. Oesper)
As IS well known, the Bunsen burner is one of the indispensable tools not only of the chemist and other related scientists but also in daily life, industry, etc. Accordingly, the course of development, which made the introduction of this burner uossible, will be of interest to many of its countless Gsers. 1n lay circles, the name Bunsen is most often associated with the invention of this burner, and even some professional workers believe that the credit belongs exclusively to him. They are ignorant of the fact that others preceded Bunsen in producing a hot, nonluminous flame by mixing air with illuminating gas. It has been established that Faraday (1791-1867) described a eas burner in 1828 in which the gas - flame was rendered nonluminous by adding considerable air. This burnera consisted of the gas inlet tube on which the jacket of a short conical outer piece could be pushed. The upper diameter of the latter was only a little greater than that of the burner tube. I t carried an outer ring provided with three arms, on which the conical outer piece mas supported. If the illuminating gas issuing from the top of the burner was lighted, and the conical jacket pushed a little above the flame by raising the ring, the luminous flame continued to come out of the cone a t first. However, if the jacket was raised still more, the generous supply of air produced a nonluminous flame with a blue inner cone. I t is readily apparent
-
Presented before the Division of History of Chemistry at the 116th meeting of the American Chemical Society, Atlantic City, New Jersey, September, 1949. BILT?., H., Z. angezu. Chem., 41,112 (1028).
that this Faraday Burner is nothing else than a close relative of the Bunsen burner. However, it did not iind wide acceptance; the time was not yet ripe for it. Here again is an instructive example of the lag that often occurs between the birth of an invention and its actual practical utilization. A. W. Hofmann (1818-92) made use of the wire screen which Davy (1778-1829) bad made the crucial feature of his safety lamp (1816). The Hofmann laboratory burner3 (Figure 1) consisted of a hollow metal cylinder with the gas inlet set into its base. The upper part of the cylinder was pierced nrith many fine openings through which the gas could stream out. The cylinder was surrounded by a ring, bearing several radial arms on which was placed a cylindrical sleeve, whose upper end wan covered with a wire zauze. Consecuentlv, " .the gas iisuina thruugh thc fine openings wa5 mixed with Iurpr proportions of :sil., u~rdthis rnixrurc l~urncdwith n bl~wflmitlill)ovc thc gauze \vifhoi~tstrikin:! hclc. 'The a n a l < - pto the J h v y safety Innil) is ob\.ioui. Hoirnunrl. n.ho scrvcd (1Xi;7+i31 as Professor at thc Royal ('ollmc of Clwmiit~y,u w l thii hurncr ill 1li.i London lul)w~torv. A pap& by Baumhauer4 (1854) makes it plain that gas burners embodying a wire gauze, but of different design than the Hofmann burner, were used in various laboratories. R. W. Elsner, a Berlin illuminating engineer, took out a number of patents (1848-56) in which he described ~~
I risure 1
~~
~
~
8 "Fehling's Hmdwiirterbuch der Chemie," (Verlag yon F. V i e weg, Braunschweig, 1886, IV Band, p. 11. 'Ann., 90, 21 (1854).
514
SEPTEMBER. 1950
the use for heating purposes of illuminating gas burned with large proportions of admixed air. The November, 1856, issue of Dingier's Polytechnisches Journalj contains an article about a new gas hurner "for the automatic mixing of gases containing hydrocarbons with atmospheric air, and their complete combustion and useful application in the household and industry xvhere heat is required." It is apparent, that the first sketch of Elmer's burner (Figure 2A) is a simple Bunsen burner, while the second sketch (Figure 2B) is a Bunsen burner provided with a handle and attached to a stand in which the vessels to be heated can be supported. The next two sketches (Figures 2C and 2 0 ) show heating arrangements consisting of three and six burners, respectively. A new laboratory was built a t Heidelberg in 1854, and Professor Robert Bunsen (1811-99) asked Peter Desaga, the university instmment maker to construct a burner which ~voulddeliver a nonluminous absolutely sootless noble, disdainful of material profit and public acclaim, flame. He was to employ the principle outlined by tirelessly dispensing rich benefits to his own and future Bunsen, but which had been known and used prior to generations." . . . "Through the introduction of the Bunsen. Furthermore, the burner was not to embody Bunsen lamp, the Bunsen burner, the labors of the chemists, formerly dependent on the charcoal fire, alcohol lamp, and bellows, have been transformed to the elegant laboratory technique of today, and the nonluminous gas flame promotes further progress in the modern general use of heating gas and the Auer light." Bunsen did not devote a separate paper to his burner, he embodied its description in the reports on his photochemical researches carried out with Roscoe. He wrote: "In these studies we used a burner7 (Figure 3) which one of us devised and introduced in the local laboratory in place of the wire-gauze burner, and which is better suited than any other contrivance for producPoggendorjs Ann. Chern. Physik., 100,84 (1857).
Figure 3
a gauze flame filter. By Easter 1855, the new Heidelberg laboratory was equipped with fifty burners of the specified type. I n May, 1855, Desaga announced that he had simplifiedthe design, and that this latter construction vas the same as the one for which Elsner secured a patent. By the end of 1855 a large number of these burners were sold. Consequently, many have justly credited Desaga with a part of the invention of the burner. Bunsen never made even the slightest effort to annex the discoveries of others. Rather, he was a man of whom one of his contemporaries-Heinrich Caro, a competent judge-wrote? "We see him, unselfish and Dinglers Polytech. J., 142, 210 (1856). Ber., 51,Zl (Sanderheft) (1918); 45, 1981 ff. (1912).
Figure 5
JOURNAL OF CHEMICAL EDUCATION
Figure 6
ing uniform flames of various intensities, color and form." Alfred Terquem (1851-87), professor of physics a t Strashurg, Marseilles, and Lille, described (1880) a modification of the Buusen burner (Figure 4).8 In this the burner tube is fastened to two rods so that it may be raised or lowered and then held in a selected position by a setscrew. The illuminating gas issues from a narrow jet, and all the air enters from the bottom and not from the side, thus accomplishing a thorough mixing. The upper opening of the burner tube is divided into four , 108 (1881). Cmnpt. rend., 91, 1484 (1880). Chem. Z a f ~ . 12,
quadrants by two plates placed perpendicular to each other. Consequently four flames come out of the tube and because of the strong rush of air, the four inner blue-green cones are drawn back into the burner tnbe and flattened. The heat of this flame is so intense that all parts of it will melt a 1.5-mm. copper wire into a bead. In 1892 Nikolaus Tech (1839-1916) constructed a burnerg (Figure 5) a t the Vienna Handelsakademie. The lower end of the burner tube is open and widerikd to a funnel shape. The tube which feeds in the gas is fitted with a conical screw valve. Above this is a thin movable plate with a knurled edge by which the burner tube can be opened or closed, i. e., the air supply can be increased or shut off completely. When the plate is screwed away from the burner tnbe, the abundant supply of air produces a roaring blue heating flame. This burner is designated by its inventor as auniversal burner since. denendine on the wurwose in mind. the tow of the tube'can'he fitted with GarGus heads to produce flames of different shapes. In the Meker burnerlo (Figure 6) (1905),the flameis dividedstillmore than in the Terquem burner. The end of the burner tube consists of a nickel grid, about one centimeter thick. This set of narrow channels, somewhat like a honeycomb, effectively prevents the flame from striking back even when the proportion of air in the mixture is quite high. Consequently, the burner delivers a very hot flame. ~~~
~
~
J. prakt. Chern., 45, 281 (1892). lo
Bull. Soe. Chim., Paris [3] 33,210 (1905).
