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ON THE USE O F TUBES O F COLORED GLASS F O R NESSLERIZING. By A. A. BRENEMAN. The idea of using tlie ordinary amber-colored window glass of lifferent shades to furnish n series of standard tints for use in the Nrssler ammonia test, occurred to me several years ago, and a note upon the subject was read at the Boston meeting of the American Association in 1880. Since then I have found, however, that the suggestion was not essentially new, and the method proposed moreover, that of holding a slip of glass of the desired tint over the mouth of a Nessler test tube filled to the mark with clear water while the tube containing the unknown quantity of ammonia is held by the side of the test tube for comparison, is open to objection. The fact that light coming to the eye after passing through the length of tlie comparison tube is modified by reflection at the surface of the colored glass, as also the fact that the colored media in the two tubes have their upper surfaces respectively in different plant a aiid at different distances from the eye, both tend to prevent a satlafactory comparison of the two tints. While these difliculties might be corrected, in part at least, by surrounding each tube with a blackened sheath or case, it has seemed more in accordance with the ordiriary method of making the Nessler test and with the princi, ples of coloiimetry in general, to introduce the colored medium be low the comparison tube. The light from this colored medium should be applied in connection with n tribe precisely like tne coniparison tube and filled to the mark with clear water; in n o other way can which is essential to a fair comparison, the qriality qf iZZzo~~ir2ntion, be obtained. The suitability of glass as the colored medium is sirnply a question of securing the proper tints. Its cleanliness, uniformit and fixity of tint render it far superior to any other substance that could be applied to this purpose. It y a s mentioned in the note referred to that the tints of commercial amber glass corresponded very well with the higher values needed among the Nessler standards, such for example as the tints given by 1c.c. of Wanklyn’s weak solution of ammoiiia (lc.c.=.OOOo~ grm. KH3), b u t it was found difficult to obtain glass matching the tints given by smalliJrquantities of ammonia a i d for values under 0.5c.c. of the standard solution, no glass of tint sufficiently light could be found. Even “flashed ”
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USE OF COLORED GLASS F O R NESSLXRIZISG.
glass which niight be Rupposeil to yield lighter tints than ‘’ pot, still too dark for the piirposv. The riianuf‘acture colored ” g l ~ s sis of g!ass is too costly nn operation to Iwi’iuit ( J C exyerimelits Iwirig 1 ‘*1,atchc.s ’- o f gl;1as i l l : d c f o r thc. I””’p0S”. U l l i C S S some irianufiictiirer could be inspirijtl \I-ith :i scicntific: interest in sucli work, or were given an order large cwougii t o warraiit tlie attempt as a matter of business. I.’niliriF i i i this direction, it occurred to me thnt a tube made from glass o f the proper h i t might answei’ the 1)urpose, and the fact that ttic bottom of sucli :t tube would be !)ZOUJ?L! suggested the means o f 1nrying its thicklieas, arid therefore its tint, to any desired extent. Scch a tul,e was found, however, to be unsoitable lor coniparison with tho c~oloi* of Nesslerixd liquid$, bef tiibr incause the yellow light coining through the siclcas ( ~ the creased tlie color given to tlie light coming through the bottom, and even when filled with clenr \rattw the qu;ility of illurninat,ion i n the two tubes was such as to forbid cornpariRoi1. T h e only suitable aondition seems to be that in whicli t h e light enters the tulw thi’ough the colored medium placed at or very near the bottom of the tube. The sides of the tube should be of c*oloi*lessglass, and the tuhe filled withclear water as mentioned ahore. These conditioiis secm t o be best fulfilled by snch tubes as are s1ion.n hew, for 1%-liicliI am in(1ebted to the cooperation of a skillful glass-blower, MI. JVilliam I3aetz. 11 short length of amber glasr tubing is fused to n longer picvc. of coloress tubing to form a tube like Lhosc. used ill Sesserlizi~ig.The bottom is flat, and the colored portion forms about oiie-fifth of t h e entire tribe. It is a matter of -onit’ dificiilty to f i i i t l glasa of proper compositioii t,o adliere readily to the ;tml)er glaw, and still more so to extend the colored part of the cyliiidrr by blowing withor~taltering it2 dinmeter. Both results have been fairly accornplished however, and slight defects shown iri tliese tiibes will be removed, no doubt, after practice in making tliern. Tt is possible, then, to start with glass tubing of a given shade and tc~weakeii rhe tint by blowing orit the tube until the desired tint i a reached. The tube is tlien cloned and flattened a t the desired distance f r o n i the junction with thc coloress glass. I n practice I have found it more simple to Iiavc. a number of sucli tubes made of various shades below a cerlain one and t o pick out from these such as corresponded exactly with the diffeient values given by the Nessler reagent with knowii quantitics of ammonia. It has been my custom for years in using Wanklyn’s method
ANALTSIS OF A MINERAL WATER, ETC.
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of water analysis, to distill off 1oc.c. at a trial, using only 1uOc.c. of the water to be tested, and all of these tubes have been made of the 1Oc.c. size, but the principle is perhaps more e a d y applicable tolargrr tubes, beclti1.e the variations of tints required would be less delicate. For very light shades I have found an amber glass with a barely perceptible olive tint to yield the best results when distended arid weakened in color as described. It should be said finally, that the junction of the compound tube causes an unavoidable ringed appearance in the tube when filled with water, but with a well-made bottom to the tube there is always a clear space within the innermost circle sufficiently large to permit of comparison with the tint of the other tube.
ON THE ANALYSIS O F A SAMPLE OF MINERAL W A T E R FROM IRONDALE, WEST VIRGILUIA. BY A. A. BRENEMAN. I have recently had occasion to examine a sample of mineral mater which, as shown by the accompanying analysis, is somewhat peculiar in composition. The water was taken from a spring 011 the property of Mr. F. Nemegyei, at Irondale, l'reston Co., West Virginia. This spriiig issues near the base of a hill in which beds of bituminous coal alternate with beds of fine clay, limonite and limestone. The coal in qome of the veins, especially in the higher parr of the hill, is very rich in pyriteR. Tlic water has a faintly acid reaction, aud in taste is weakly a%tringerit. Its color is perceptibly yellowish in thick layers. Analysis yields the following results expressed in grains per U. S. gallon : Calcium Sulphate - - -.- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 60.417 Aluminium " _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _11.371 _______ Potassium " _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ -_-_- -______ __ __ _ _. _6.764 __ Magnesium (' _ _ _ _ _ - - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _4.335 _____ Manganese '' _ _ - - - . . - - -. _ - --.---- - - - -- ^ - -_-_ __ _ _ 2.851 ._ Ferrous (?) " ___._ - - ___ __- __ _ -_ _ __ _ _0.336 _ ___ Cobaltous " _ _ . __ _ . _ _ _ _ _ __ _ _ _ _ _ ._ _ _ _ _ _ _ _ _ Trace - - - - - - - - - - - - 1.361 Sodium Chloride- - - - - - - - - - - - - - Silica, Si 0,- -- ---- ---- ------ -- - - 1.445 Nitric Acid _ _ _ _ __ .---- - _ _- - - - _- - _ _ - Trace -- -__ 10.259 Organic and volatile matter -
_________ _________ - - - __ -____ __ __ ____ __ __ ____ ____ ____ _________ _ _ _ _ _ _ _ _ _ . _ __ _ _ _____ _ _
