I am a power of one hundred and fifty pounds of steam. Up to that pressure of steam I

I am a power of one hundred and fifty pounds of steam. Up to that pressure of steam I can be easily worked up to one hundred and horse-power. I am soft at high pressure, but at low power I can be easily worked up to high horse. I am soft at low power, but at high pressure I can be easily worked up to high horse. I am easily kept up to my power, but not easily increased beyond it. I am soft at low power, but at high pressure I can be easily worked up to high horse. I am easily kept up to my power, but not easily increased beyond it. I am easily worked up to high horse, but not easily worked up to high power. I am easily worked up to high horse, but not easily worked up to