What does the Rømer scale measure?

The Rømer scale is a no longer used temperature scale. It is considered to be the earliest calibrated temperature scale with 0 degrees being the temperature of brine, 7.5 degrees being the temperature of freezing pure water, and 60 degrees being the temperature of boiling water. So there are definitely similarities to the Fahrenheit scale with brine being 0 degrees.

Daniel Gabriel Fahrenheit, inventor of the Fahrenheit scale, visited Copenhagen in 1708. While there, he met Rømer and learned about his work with thermometers and scales. Rømer also told Fahrenheit that demand for accurate thermometers was high. The visit ignited a keen interest in Fahrenheit to try to improve thermometers. By 1713, Fahrenheit was creating his own thermometers with a scale heavily borrowed from Rømer that ranged from 0 to 24 degrees but with each degree divided into quarters. At some point, the quarter degrees became whole degrees and Fahrenheit made other adjustments to Rømer's scale, modifying the freezing point from 7.5 degrees to 8, which, when multiplied by four, correlates to 32 degrees on Fahrenheit's scale. The 22.5 degree point would have become 90 degrees, however, by 1713, Fahrenheit rounded this up to 24 degrees–96 when multiplied by 4–in order to make calculations easier.

https://en.wikipedia.org/wiki/R%C3%B8mer_scale