REPORT
Pictured is a hypothetical complex ion with a negative charge of two, assembled from the latest Godfrey Models, which could be called "Iron (III) aquo bromo cyano fluoro thionophosphate."
You can construct any organic form that can exist.. . many inorganic forms, too with
WILL
GODFREY MOLECULAR MODELS Best representation of Van der Waals' and covalent radii. Realistically shows true molecular mobility, even demon strates vibratory modes responsible for infrared spectra of molecules. No tools required. Simple quick hand connec tions only. Made of colorful polyvinyl chloride, flexible and compressible as actual atoms.
( Ι Α Ι Λ
Will No. 20140N—Basic Kit with 100 atoms only
4 "
(assortment of H, C, N , O , CI a n d S atoms i n 11 valence states} includes 12-page
manual
NEW ATOM MODELS . . . add these to your basic kit and you can represent 35 elements in 65 valence states. WILL NO. 20142N 4 ea. of fluorine, bromine, iodine
$goo
You can show hydrogen bonding (water tetramer on left} or strained ring systems (camphor on the r i g h t ) .
WILL NO. 20143N 4 ea. of thionyl sulfur, tetrahedral sulfur, nitrile nitrogen
$900
WILL NO. 20144N 4 each of pentavalent phosphorous cap, tetrahedral silicon, trigonal boron
$12 00
WILL NO. 20145N 4 each of metal atoms Nos. 1, 2, 3 and 4 and trigonal oxygen . . . .
$1500
WILL
CORPORATION and subsidiaries • • • • • •
Rochester 3, Ν. Υ. New York 52, Ν. Υ. Buffalo S, N. Y. Atlanta 25, Ga. Baltimore 24, Md. So. Charleston 3, W. Va.
Circle No. 124 on Readers' Service Card 32 A
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ANALYTICAL CHEMISTRY
of completely reconditioning the in strument, extending a new instru ment warranty, and then having to sell a t less than the m a r k e t price of a new unit. Any design changes must be included in the warranty, which adds to the cost and decreases return in the investment. RCA and Baird-Atomic accept their own instruments in trade. With respect to instruments made by other companies, however, they handle these situations on an indi vidual basis. Baird-Atomic recon ditions and sells trade-in items. Varian has not established a firm policy regarding trade-ins. Gen erally it does not intend to accept trade-ins. If, however, the need for short-term leases develops, it may accept trade-ins to build up a pool of used instruments to meet this demand. Trade-in equipment could be re conditioned and, if not placed in a used instrument pool, could be sold at reduced rates to educational in stitutions. The final decision would be based on circumstances prevailing a t the time and would be governed in part by the nature of the instrument—that is, its porta bility and useful life. Varian can not visualize a situation where it would accept another manufac turer's instruments in trade. Varian feels t h a t trade-ins are good for the customer, as they re duce his outlay for new instruments and facilitate his disposal of old instruments. They arc good for universities and research groups who receive instruments at low prices. The manufacturer, how ever, has problems of warehousing, distribution, and inventory. These functions all detract from his major purpose in life—to develop the most advanced analytical instrumenta tion possible. Coleman, Emil Greiner, and N u clear-Chicago do not sell or lease used equipment, so they generally do not accept trade-ins. In rare instances where Emil Greiner does accept a trade-in, the trade-in value is so nominal that it is donated as a tax-deductible contribution to some school or institution. The obso lescence factor, Nuclear-Chicago feels, rules against its accepting trade-ins.
