MICROCHEMICAL KITS R.D. COOL University of Akron, Akron, Ohio
D
IFFERENT types of boxes or blocks have been proposed for reagents and equipment for chemical microscopy and microchemical qualitative analysis (27, 28, 29, 30, 31, 32, 33, 34, 35, 36), and several are available from supply houses in this conntry.' For the past ten years it has been necessary for the writer to keep his microchemical equipment so that it could be moved readily about the building in order to protect it from loss and dirt. The first improvement over the original pasteboard box was made by fitting a frame inside a cigar humidor2 to support a reagent
and two straps, was used. Although this arrangement proved satisfactory for a limited amount of equipment it soon became inadequate as additions were made. The field kits of Putnam, Roberts, and Selchow (38)
seemed to meet the requirements better than other types described but they had been made up locally4 and were not regularly available on the market. For the'past five yean a machinist's chest (Figures 1, 2, and 3), thoroughly painted inside and out with a block holding sixty reagents (37)for chemical microscopy (Figure 1). The space under the block was used for high-grade spar varnish, has been giving excellent semsmall apparatus, and eight "cobalt" bottles3 for solu- ice. The upper part of the chest holds the reagents tions fit in blocks around two sides of the reagent block. and the construction is such that the apparatus conWhen the box had to be transported for any consider- tained in the drawers below is completely isolated from able distance a luggage carrier, consisting of a handle the reagents in the top of the chest. As shown in Figure 2 the reagent vials fit into five blocks. Four ' R. P. Cargille, New York City, No. 220; Eimer and Amend. of the blocks hold two hundred twenty glass-stoppered New York Cily, No. 26098,28357,28358; Microchemical Service, vialss and the fifth holds six ebonite vialsVor compounds
Douglaston, N. Y., No. 1280, 1530, 1540, 1550; E. H. Sargent and Company, Chicago, No. 5-46525; and Will Corporation, Rochester, N. Y., No. 14622, 14627,14633,14634,18502. Sunnested bv one of the writrr'sassociates at the University of Pennsfimnia. Arthur H Thomas Company, Philadelphia. No. 2252.
"Private communication, Roberts, February, 1934. Micrachemical Service, Douglaston, N. Y., No. 3790; Arthur H. Thomas Company, Philadelphia, No. 9800, 2-ml.; Will Corporation, Rochester, N. Y., No. 14632. Microchemical Service, Douglaston, N. Y..No. :ifiOO.
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of fluorine and reagents for sodium. Most of these blocks were on hand when the chest was purchased and offer no advantage over a single large one, the use of which would increase the capacity by a t least thirtythree vials. Rather than employ a key chart, as is usually suggested, it has been found more convenient to put small labels on each vial, paint the labels with a clear lacquer, and arrange the reagents alphabetically.
The location of the vials is soon leamedtfrom using them, and no difficulty is experienced in finding quickly a particular reagent. Moreover, the labeled vials may be transferred without confusion to other blocks when relatively small numbers are being used, as, for example, in procedures such as those of Davison (7) or Short (Zl), or even procedures which require a somewhat larger number, as those of Burkhard (3), Kramer (16), or Staples (22). The small box shown in Figure 1, which was made by removing the partition from a playingcard box and inserting a block having holes for twelve reagent vials, has proved quite convenient when studying procedures which do not require a large number of solid reagents, and the cover offers protection from dust when the reagents are not being used. Small blocks without covers, bored for one, three, and five vials (Figure 3), are used to hold temporarily reagents which will be used repeatedly during a single working period. Most of the reagents in the chest are solids. Reagents which sublime readily or give off fumes are kept
in sealed tubes or the glass-stoppered vial is placed in a second larger vial with a tightly fitting plastic screw cap. The vials contain not only the solid reagents required for carrying out qualitative tests according to
microchemical procedures recommended by various authors (1,2,3,4,5,7,8,9, 10, 13,16,17,19,20,21,22, 26), but also reference material, including compounds of most of the rare elements as well as all the more common ones, which may be used for making comparisou or check tests. Some sugars, starches, and fibers are also included, but permanent slides make up the greater part of the reference material for the last two. With the exception of some reagents for spot tests (7, 11, 12, 14, 15, 18, 23, 24, 25, 26), solutions are kept in 15-ml. bottles which have ground-in droppers7 and fit into wooden blocks (Figure 3). The bottles which do not have extra caps with ground joints have the
' Arthur H. Thomas Company, Philadelphia, No. 2252,2255
neck and dropper covered with a shortened test-tube, or glass tumblers are placed over the whole bottle. It is highly improbable that other people doing work of this kind will be in a place so dirty as the location of the writer, and he can recommend these precautions against dirt as having served unler the worst conditions. Solutions of some of the reagents for spot tests have been kept satisfactorily in dropping bottles with plastic
screw capss and vials with applicator rods.8 Blocks containing these vials will fit in the chest and may
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*Arthur H. Thomas Company, Philadelphia, No. 2248-B; Wiikens-Anderson Company, Chicago, No. W-1130, W-7905, ""nc ""-,>"".
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Central Scientific Company, Chicago, No. 10555; Fisher Scientific Company, Pittsburgh, No. 20-095, 50 X 19 mm.; Arthur H. Thomas Company. Philadelphia, No. 2253-C. 50 X 19 mm.
be kept there if a reduction is made in the number of solid reagents. The material kept in the drawers of the chest (Cf., Figure 2) includes most of the special equipment required for inorganic qualitative microanalysis on the microscope slide, in capillaries or centrifuge cones, and by spot tests, as well as that for separations and preparative work on the micro scale. No provision is made in the chest for the microscope, which is best kept and transported in its special case, or for standard apparatus found in every laboratory. The chest as described represents a sizable investment, but the equipment gradually accumulated over such a long period of time, as one microchemical procedure after another was studied, that it has not proved embarrassing even to a college instructor's income. Moreover, it has a larger capacity and greater flexibility than microchemical boxes on the market, and a t the same time its construction is much stouter and the proportionate cost is less. The writer prefers vials as described for reagents in the chest, but the cost may be lowered considerably by using screw-cap vials1° or still more by using serological test-tubes" with corks, such as be uses in large numbers for storing specimens or chemicals which are rarely used and are not of the highest purity. He has been informed by people who have used the screw-cap vials for several years that they have been satisfactory, and he also knows of instances in which corked vials have been used for student instruction with apparent satisfaction. The microscope stand shown in Figure 3, including the mirror, was obtained a number of'years ago from a laboratory supply house for $2.50.. flew strain-free 32-mm. and 16-mm. objectives and a 10X eyepiece, which may be used with any good polarizing microscope, brought the total cost of the microscope to $21.50. Used optics would have brought the cost even lower. Such an outfit, even though supplemented with "Polaroid," is not to be considered in place of a good polarizing microscope, but is shown just to indicate a t what small cost a microscope with good optics and suitable for a great deal of work can be obtained. The stand is small and much more comfortable to use than the newer larger stands, and the writer always uses it unless be needs polarized light or high magnification for which the fine adjustment is no longer sensitive enough nor the illumination satisfactory. The two single-hole blocks of equal weight (Figure 3) are used to balance centrifuge cones because the latter vary in weight so much that a balance is not obtained merely by adding equal volumes of liquid to each tube. The oil-can microburner shown in the same figure has been described elsewhere (6). I:. H. Sar~rntand Company. Chicago. No. S-46,535; Arthur H . Thomas Comyan). 1'Liladcll~hiil,No. qRW-E. 2-ml Fijhcr Sricntitir C v m p m y . P j t f d ~ ~ r gSl o~ . 14-!B5.
LITERATURE CITED
(1) BEHRENS-KLEY."MikTochemische Analyse," Voss. Leipzig. 1915.368 pp.
3rd
ed..
(2) BENEDETTI-PICHLER AND SPIRES. "MicmtechRiql~e of inorganic qualitative analysis," Microchemical Service. Douglaston, N. Y.. 1935, 180 pp.
BURKHARD. "Qualitative mikroskopische Analyse." Schulthess, ~urich,-1933,49pp. CHAMOT,"Elementary chemical microscopy," 2nd ed.. John Wiley Pi Sons, Inc., New York City, 1921,479 pp. AND MASON, "Handbmk of chemical microscopy." CHAMOT Tohn Wiley Pi Sons, Inc., New York City, 1931. Vol. 11. 411 PP. COOL. "An inexpensive microburner," Chemist-Anelysf, 28, 23 (1939); DAvISON, Field tests for minerals." Chemical Publishing Co., New York City, 1937, 60 pp. DONAU, "Die Arbeitsmethoden der Mikrochemie." Franckh'sche Verlagshandlung. Stuttgart, 1913, 70 pp. EMICH."Lehrhuch der Mikrochemic." 2nd ed., Bergmann. Miinchen, 1926,273 pp. EMICH-SCHNE~DIIR, "Microchemical laboratory manual." John Y l e y & Sons, Inc., New York City, 1932, 180 pp. Fem,, Qualitative Analyse mit Hilfe von Tupfel-Reaktianen," 3rd ed., Akademische Verlagsgesrllschaft. Leipzig, 1938, 554 pp.; "Tiipfelreaktionen," Mibochemie. 8, 356-74 (1930). FEIGL-MATTHEWS, "Qualitative analysis by spot tests." 2nd English ed. translated from 3rd German ed.. Nordeman Publishing Co.. New York City. 1939,462 pp. GARNER,''Induqtrial microscopy." Sir Isaac Pitman and Sons, Ltd., London, 1932, 389 pp. GUTZEIT,"Sur une mCthode d'analyse qualitative rapide. I . De quelques r&ctions specifiques et spCciales des cations et anions les phts usuels," Helu. Chim. A d a . 12, 713-40 (1929); "11. Methode d'analyse rapide, 'A la touche' dcs cations et anions les plus usuels." ibid., 12, 829-50 (1929). HELLER AND KRUNHOLZ,"Beitrage zur systematischen Tupfelanalyse," Afikrochamic. 7, 213-22 (1929); HELLEn. ibid., 8, 3 3 4 0 (1930). KRAMER, "Mikr~nalytische Nachweise anorganiqcher Ionen," Akademische Verlagsgesellschaft. Leipzig. 1937. 35 PP. LINDSLEY, "Industrial m i ~ m s ~ o p y Wm. ," Byrd Press. Richmond. Va., 1929, 286 pp. VAN N l s u w e ~ s u R c AND DULFBR,"A short manual of systematic qualitative analysis by means of modern drop reactions." 2nd ed., Centen. Amsterdam. 1933,88 pp. PUTNAM, ROBERTS. AND SELCHOW. "Contrib~tiomto determinative mineralogy," A m . I. Sci.. 15, 89-102. 253-61, 421-30. 45r~fi0(1Q08).
SCHOORL."BeitrZge rur mikrochemischen Analyse. I. Allgemeine Bemerkungen," Z. anal. Chem.. 46, 658-71 (1907); " I . Analyse der Silbergruppe," ibid., 47, 209-34 (1908); "111. Die Gruppe der sauren Sulfide (Arscn. Antimon, Zinn)." ibid., 47, 367:XQ (1908); " I . Die Gruppe der basischen Sulfide." rind., 47, 729-54 (1908); "V. Analyse der Eisengruqpe." ibsd., 48, 209-31 (1909); "VI. Die Gruppc der Erdalkalimetalle' (Baryum. Strontium, Kalzium)," ibid., 48, 401-15 (1909); "VII. Die 'Restgryqpe' (Magnesium, Lithium, Kahum, und , 593-611 (1909); "VIII. Die unNatrium)," ~ b z d . 48, liislichen Substanzen," ihid., 48, 6 6 5 7 8 (1909). SHORT,"Microscopic determination of the ore minerals," U. S. Geol. Survey, Bull. 825 (1931). 204 pp. STAPLES,(a), "Mineral determinations by microchemical methods," A m . Mineral., 21, 613-34 (1936); ( b ) ROGERS,"Introduction to the study of minerals," The McGraw-Hill Book Co., Inc., New York City, 1937, pp. 243-59. TANANAEV, "Qualitative Analyse der Elemente der 1-111 Gmppe bei ihrer gemeinschaftlichen Gegenwart mit besonderer Beriicksichtigung der Tiipfelanalyse," Z. anorg. allymz. Chem.. 140, 32034 (1924); "Micro methods" (Russ.). 3rd ed.. Ontvu, Kharkoff and Kiev, U. S. S. R., 1933, 128 pp., supplement of 8 pp. with 91 tests AND SCHAPOVALENKO. "Tupfelin color; TANANAEV Methode zum Nachweis der Anionen," Z. anal. Chem.. LOO. 343-55 (19351. T O U G ~ N O P F .' c ' ~ ~ reactions S organiques dans l'analyse qualitative minCrale." Ceuterick, Louvain. 1930, 107 pp. W a ~ s o w "Cnlnr -... rpartions in the microchemical determinations of minerals," A4ineralo.c. Map., 24,21-34 (1935). WILSON,"An introduction to microchemical methods." Chemical Publishing Co., New York City, 1938, 196 pp. Reference 1, p. 25. Reference 2, pp. 168. 170. 174. Reference 4. D. 146. Reference 5. 6. 22. Reference 9. pp. 3 6 7 Reference 10. p. 18. Reference 17. D. 51. Reference 19: b. 96 Reference 22a. p. 617. Reference 226, pp. 244--5. Reference 5. D. 401. .. Reference 19: p. 96. ~
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