Gases can adsorb on (stick to) or absorb in (dissolve in) solids. Measuring this gas-solid interaction is critical to understanding permeation through membranes. Barometric, a.k.a. pressure decay, sorption instruments work by introducing a known amount of gas into a sample chamber of known volume. Readings from two pressure transducers are analyzed by computer to determine the amount of gas added to the chamber and the amount sorbed by the solid. Pressures from 0-200 bar can be tested. Because solubility is a strong function of temperature, the systems are housed in temperature-controlled circulating baths. Seven of our systems can operate between room temperature and 80 C; two can operate below zero. They were created by AMPM students and staff, using commercial temperature baths and parts sourced from America and Saudi Arabia.