dipping refractometer
Date: 1930-1940
Inventory Number: 1996-1-0682
Classification: Refractometer
Maker: Bausch & Lomb Optical Company (1853-present)
Maker: Taylor Instrument Companies (1851 - 1992)
Cultural Region:
Place of Origin:
Dimensions:
case: 12.5 x 43.4 x 14.6 cm (4 15/16 x 17 1/16 x 5 3/4 in.)
Accessories: case; thermometer; immersion prisms (5); calibration cells (3); other prism
Bibliography:
Catalog D-111: Scientific Instruments
Description:
The instrument consists essentially of a telescope, a compensator and the immersion prism. The compensator is found inside the body tube and is made of a single Amici prism. The immersion prism is mounted at the end of the instrument and it is made of crown glass. There are five different ones in this set, each covering a narrow (and overlapping) range of measurement:
A: 1.32539 to 1.36640
B: 1.36428 to 1.40608
C: 1.39860 to 1.43830
D: 1.43620 to 1.47562
E: 1.47320 to 1.51335
The set also comprises a thermometer in its balsa case (range of 15 to 25°C) and three calibration cells in cylindrical cardboard boxes. There is also a small bottle of alpha-bromonaphthalene, which was applied to the prism surface when measuring solids instead of liquid substances. The hook found on the instrument was used to suspend it over the constant temperature control unit (not shown here).
A: 1.32539 to 1.36640
B: 1.36428 to 1.40608
C: 1.39860 to 1.43830
D: 1.43620 to 1.47562
E: 1.47320 to 1.51335
The set also comprises a thermometer in its balsa case (range of 15 to 25°C) and three calibration cells in cylindrical cardboard boxes. There is also a small bottle of alpha-bromonaphthalene, which was applied to the prism surface when measuring solids instead of liquid substances. The hook found on the instrument was used to suspend it over the constant temperature control unit (not shown here).
Signedon refractometer: BAUSCH & LOMB OPTICAL CO.
on thermometer: Tycos
on thermometer: Tycos
FunctionA refractometer is a precision instrument used to measure the index of refraction of liquid substances as well as the mean dispersion of fluid, plastic and solid bodies.
The dipping or immersion type refractometer is designed to cover a small index range with a higher accuracy than is possible with the Abbe refractometer (see, for instance, 1992-1-0001 and 1996-1-0533). According to the B&L catalogue: "[This] Dipping Refractometer is designed particularly for the measurement of solutions in bulk, but, with accessory prisms, may be used where only small quantities are available and may also be used for solids whose indices lie within the range. [...]
It is quite essential, if accurate measurements are to be obtained, that temperature be controlled carefully. For this purpose there is offered a constant temperature control unit similar to that described for the Abbe Refractometer."
This temperature control unit is a rectangular tank in which are suspended glass beakers containing the solutions under investigation. Under the tank is a mirror providing light to the system. The tank was linked to a heater. An image of such a tank (without the heater) can be seen on the following website.
The dipping or immersion type refractometer is designed to cover a small index range with a higher accuracy than is possible with the Abbe refractometer (see, for instance, 1992-1-0001 and 1996-1-0533). According to the B&L catalogue: "[This] Dipping Refractometer is designed particularly for the measurement of solutions in bulk, but, with accessory prisms, may be used where only small quantities are available and may also be used for solids whose indices lie within the range. [...]
It is quite essential, if accurate measurements are to be obtained, that temperature be controlled carefully. For this purpose there is offered a constant temperature control unit similar to that described for the Abbe Refractometer."
This temperature control unit is a rectangular tank in which are suspended glass beakers containing the solutions under investigation. Under the tank is a mirror providing light to the system. The tank was linked to a heater. An image of such a tank (without the heater) can be seen on the following website.
Primary SourcesBausch & Lomb, Scientific Instruments, Catalog D-111 (Rochester: Bausch & Lomb, ca 1940), 216-218.
ProvenanceFrom the Department of Chemistry, Harvard University.