Step 1: Understanding the Concept
The question asks to identify a colour medium that is typically applied without a brush.
Step 2: Detailed Explanation
Water colour and Oil colour are paints that have a liquid or paste-like consistency and require a brush to be applied to a surface.
Pastel colours come in the form of sticks or crayons. They are a dry medium. The artist holds the pastel stick and applies the colour directly onto the paper or canvas. Blending is often done with fingers, a cloth, or a tool called a stump, but the initial application does not require a brush.
Step 3: Final Answer
Therefore, pastel colour is the medium applied without using a brush.