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dashpot mechanisms were filled with lOW-40 motor oil. drives were operated for one week for timing accuracy before test initiation, and maintained an accuracy of per week throughout the test program. The gages and related experimental equipment were operated in an enclosed, unheated hallway area between Bureau of Reclamation mobile offices at the Miles City, Montana airport (see Figure 1). The chart checks :!:. 5 minutes While the hallway area was not heated, the entrainment of air from adjacent offices with passages of personnel and associated opening and closing of doors raised temperatures somewhat above outside ambient levels. AI though outside \lrind effects were totally removed from the experimental setti.ng, passage of personnel or rapid closing and openin<g of office doors may have resul ted in internal drafts. However, such drafts are bel ieved to have had minor impact on the gages. The gages were set on a table with legs: anchored di rectly to the ground (see Figure 2), which prevlented floor vibrations from being transmitted to the gage mechanisms through the table legs. Further vibration control was obtained by placing the gages on a corrugated cardboard sheet glued to a 3-inch thickness of foam rubber. This limited disruptions of the me~chanisms to the influence of internal building drafts. An elevated reservoir system was constructed and mounted to feed into the gages. First a pressurized s:ystem was tried, but because of the inconsistent flow rates obta.ined, a gravity system was finally designed to serve as the precipitation feed. Two plastic water bottles (l gallon) with a water-ethylene glycol mixture (approximately 80%/20%) were supported from the 6-foot, 10-inch ceiling of the hallway. Thesle rese~rvoirs had vented medical intravenous (IV) units insertd into> the base of the plastic reservoirs. From the IV inse:rts 1/8-inch tubing carried the fluid through a regulator clamp to a position above the raingage catch buckets, where it was allowed to drip into a beaker within the raingage catch buclcets. The IV tube was elevated to allow a separate control beaker to be swung into posi tion below the IV feed and above t.he raingage to intercept the flow into the gage. This enabled measu.rement of the flow rate by weighing of the intercepted catch and division by the period of time that the flow was intel~cepted. Due to the slow rates used for the tests, individual drops could be counted. The interval of time between drops was observed and recorded for all tests and used as an approximate indi(~tor for flow-rate adjustment. The Belfort gages were calibrated prior to test activities in accordance with standard calibration practices. Calibration results, summarized in Table 1, show that accu~acy within:!:. 0.03 inch was obtained over the full 12-in<::h gage span. The gages were calibrated for a temperature environment of approximately 3