Barometers are instruments that are designed to measure the differences in air pressure.
(Barometers; are; instruments that are designed to measure the differences in air pressure) (instruments; are designed; to measure the differences in air pressure) (instruments; to measure; the differences in air pressure)
Barometers instruments instruments
are are designed to measure
instruments that are designed to measure the differences in air pressure
to measure the differences in air pressure
the differences in air pressure