Some time ago my boiler engine was frozen up in a cold snap, and I wished to give my boiler a hydraulic test before steaming up again, to see if it was fit for business. I had no force pump or apparatus of any kind, yet I tested the boiler to the desired pressure, 100 pounds. I have had conversations with engineers since then, and not one of them could tell me how to make such a test without any apparatus, so I believe the idea may be useful for Handy Man's Workshop. I filled the boiler completely with water, leaving no air space whatever, then built a small fire under the boiler, and as the cold water warmed up and expanded, I watched the pressure gage rise until it reached the desired testing pressure, when I opened one of the try cocks, allowing a small quantity of water to escape and relieve the pressure. Having found things O. K., I drained water from the boiler to the proper level and proceeded to get up steam.