How was this measured using the technology of the 1880's?

Pressure inside the eye is measured using one of several devices.

Land area in particular was measured using the ken as a basis.

It can be measured directly using the quantum Hall effect.

Sexual motivation can be measured using a variety of different techniques.

It can be measured in plant cells using the Pressure bomb.

Proportions are often measured using head length as a guide.

This was always measured using three full jerry-cans of water.

The speed would have been measured using a knot log.

Most properties are measured using a number and a unit of measurement.