An inexpensive mercury thermoregulator - Journal of Chemical

This inexpensive mercury thermoregulator requires a 50 mL pipet, a short piece of thick-wall capillary tubing, a short piece of platinum wire, mercury...
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VOLUME 33, NO. 3, MARCH, 1956

pears below. The following have been appointed to serve as the Eighteenth Summer Conference Committee: C ~ h a i n n for a ~ Arrangements. Louise 0. C. Swenson, English High School, Lynn, Massachusetts. C h i r m a n for Pmgram. Clinton S. Johnson, Rhode Island College of Pharmacy, Providence, Rhode Island. Represenkztive of Host Imtitution. Harold A. Iddles, Chairman, Department of Chemistry, University of New Hampshire, Durham, New Hampshire. Registrar-Treasurer. Irwin H. Gawley, State Teachers College, Upper Montclair, New Jersey. Secretmy. Charles M. Wheeler, Jr., James Hall, University of New Hampshire, Durham, New Hampshire. Publicity. Marguerite J. Houlihan, Chainnan, Lincoln Junior High School, Medford, Massaohusetts. Social. Beatrice C. Gushee, Chairman, Smith College, Northampton, Massachusetts. Ezhibib. Benjamin R. Graves, Chairman, South Portland High School, south Portland, Maine. Motion Picture. Norman W, Lafavette. Chairman, Hamden High School, Hamden, ~onnecticui. Guest Actiuities. Mrs. Marco H. Seheer, Chairman, Nashua, New Hampshire. Hospitality Chairman. George D. Hearn, Classical High School, Worcester, Massachusetts.

The following additional committee members with their committee assignments were also announced: Assislant Registrar-Treasurer. Dr. and Mrs. Ralph P. Seward, Pennsylvania State University, University Park, Pennsylvania; Mrs. Irwin H. Gawky, Upper Moutolair, New Jersey. Publicity. David C. O'Keeffe, West High School, Manchester, New Hampshire. Proyrarn. Carl P. Swinnerton, Pomfret School, Pamfret, Cannecb iout; David L. Davidson, Technical Operations, Inc., Arlington, Massachusetts. Guest Aetiuities. Mrs. Carl P. Swinnerton, Pomfret, Connecticut. Social Evenings. Mrs. Maryalice Moore, Taunton High School, Tauntou, Massachusetts; Lorne F. Lea, St. Paul's School, Conoord. New Hamoshire: Mrs. Phyllis A. Brauner, Simmons College, Boston, ~.&saohusetts. Theate7 Pavty. Angela M. Travato, Exeter High School, Exeter, New Hampshire. Picnic. Guy F . Burrill, Keene High School, Keene, New Hampshire. Ezhibits. Edward M. Collins, Denison University, Granville, Ohio. Speeke~Hospitality. George D. Hearn, Classical High School, Worcester, Massachusetts. Member Hospitalzty. Mrs. Thyra Jane Foster, Cohntry High School, Coventry, Rhode Island.

To aid the 'committee in maintaining the high standards set a t previous summer conferences, a "Manual for Summer Conference Committees" has been assembled by Professor Robert D. Eddy, Tufts University, who was secretary of the Seventeenth Summer Conference. It contains recommendations and procedures

found by previous committeemen to be helpful. It was distributed to chairmen by Miss Swenson. LEALLYN B. CLAPP Secretary

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AN INEXPENSIVE MERCURY THERMOREGULATOR LOUIS W. CLARK Saint Joseph College, Emmitaburg, Maryland

COMMERCIAL mercury thermoregulators for use with electronic relays for thermostat water or oil baths cost approximately $40. Furthermore they are usually quite fragile, easily broken, and may he difficult to set. A simple, home-made thermoregulator, easily constmctedof inexpensive materials, has been used in this laboratory for the past year. Bymeansof this regulator, in a well insulated and efficiently stirred oil bath, any desired temperature up to shout 170" can be maintained within =tO.OlO. Theonlymaterialsneeded are a 50-ml. pipet, a short piece of thickwall capillary tubing, a short piece of platinum wire, mercury, and a Bunsen burner. The lower stem of the pipet is heated in the Bunsen burner near the bottom of the bulb; it is drawn out to a fine capillary, and a short piece of platinum wire is sealed into the bulb. The upper stem of the pipet is filed off about five cm. above the top of the bulb, and a short piece of thickwall capillary glass tubing is sealed on. A few centimeters beyond the seal the thick-wall capillary tubing is heated, pulled out slowly to a fine capillary about 10 cm. in length, and filed off. I n the figure, A is the point of junction of the truncatedupper stem of the pipet and the thick-wall capillary tubing, B is the bulb of the pipet, and Cis the platinum wire sealed into the bottom of the bulb. The bulb is filled with clean mercury and a short piece of platinum wire is inserted in the opening at the top of the thin capillary. The two wires are connected to the two terminals of an electronic relay which operates the heater. The method of setting is obvious.

FAIRY STORY AUTHOR DISCOVERED T m article "A fairy story for chemists" on page 637 of the December issue was written by Carl Honaker, Associate Professor of Physics and Chemistry, Tennessee Wesleyan College, Athens, Tennessee. The story was first printed in the May, 1954, issue of The Blanched Chain, section publication of the East Tennessee Section.