The Hawaiian Volcano Observatory celebrated the 30th anniversary of Mauna Loa's last eruption (in 1984) on March 25, 2014, underscoring that it has been a realtively quite 3 decades at the world's largest active volcano.
A tiltmeter, is a type of instrument used to detect any kind of tilt in the structure to which it is attached. Most tiltmeters use an air bubble in a liquid-filled tube, much like a typical carpenter's level, but are equipped with sensitive electronics that can detect even the tiniest change in tilt. They either sound an alarm or transmit the data to a remote monitor or other device.
An acidometer (sometimes spelled acidimeter) is a hydrometer used to measure the specific gravity of an acid. Salinometer. A salinometer is a hydrometer used to measure the salt content of the feed water to a marine steam boiler. Use in soil analysis A hydrometer analysis is the process by which fine-grained soils, silts and clays, are graded.