Convert from crith to slinch

Unit Definition (crith)
The crith is a unit of mass sometimes used in the physics and chemistry of gases. The crith is equal to the mass of a liter of hydrogen at standard temperature (0.01°C) and pressure (1 atmosphere); this is about 89.885 milligrams. The name comes from an ancient Greek word for a barleycorn.

Unit Definition (slinch)
The slinch is a unit of mass invented by the U.S. National Aeronautics and Space Administration (NASA). The unit is part of a system based on the pound of force and the inch. One slinch is the mass accelerated at one inch per second per second by a force of one pound; thus the slinch equals exactly 12 slugs or about 386.088 pounds (175.1268 kilograms). The word is a contraction of slug-inch. In the U.S. military aircraft industry, this unit is sometimes called a mug. It has also been called a snail.