The method to liquify the atmospheric gases is called "fractional distillation". This method involves cooling the gases under high pressure and then separating them based on their different boiling points. The process can be broken down into the following steps:

1. Compression: The atmospheric air is compressed to a high pressure, typically between 150 and 200 atmospheres (atm). This increases the density of the gas, making it easier to cool and liquefy.

2. Cooling: The compressed air is then cooled using a heat exchanger or a refrigeration system. This causes the gases to condense into a liquid state.

3. Distillation: The liquid air is then distilled in a series of columns to separate the different gases based on their boiling points. Each gas has a specific boiling point, so it will evaporate and be collected separately as the temperature is increased.

The main gases that can be liquified using fractional distillation are nitrogen, oxygen, argon, and carbon dioxide. These gases have relatively low boiling points and can be easily separated from each other. Other gases, such as helium and neon, have much lower boiling points and require specialized techniques to liquefy.