By popular request, here is the address for Cargille, who make the refractive
index standard immersion oils:-

Cargille Laboratories
55 Commerce Road
Cedar Grove
NJ 07809
U.S.A.
Tel. (201) 239-6633

If they don't have the exact value you want, you can mix together the nearest
neighbors in the series in the right proportions to exactly hit the required
value.

Another approach is to do what the forensic labs do and use an oil which
changes rapidly as it is warmed up.  Ramp up the temperature until the
observed structure loses its refractive edge, then read off the corresponding
RI on a temperature/RI calibration curve.

Does anyone know of a microscope incubator with a wide enough temperature
range to do this routinely?


David Carter
General Manager

Meridian Instruments
Steeped in solutions
2310 Science Parkway
Okemos MI 48910