On the ranges in Germany before we could put fuel tanks in we had to create a bund wall of soil then lay a big sheet of grey rubber sheeting in to stop any fuel spills from the tanks going into the soil. Every morning when the sun got up there was frogs, toads, snakes and all manor of other creatures laying on the sheeting warming up in the sunlight. i had the bright idea of freezing a few to see what happened, So a couple of frogs in a tin bucket and down to the Liquid Oxygen tank, Close the vent valve, open the pressure raising valve, when the gauge got to about half way, close the pressure