Which step is part of the dry gum method?

• A. 2 parts water added before any oil
• B. 1 part acacia triturated with 4 parts oil in Wedgewood mortar
• C. Mix water and oil then add gum
• D. Emulsion transferred to graduate and made to volume with water

Answer: (B)

In the dry gum method, the gum is first dispersed in the oil to form a thin paste, creating the primary oil-in-gum emulsion before any water is added. This approach relies on the gum acting as the emulsifying agent and the oil-gum mixture being the initial dispersed phase. Triturating acacia with oil in a Wedgewood mortar achieves that thorough dispersion and paste formation, which is why this step is consistent with the dry gum method.

Adding water before oil would be characteristic of the wet gum (English) method, while mixing water and oil first or simply adjusting volume afterward does not reflect the initial emulsification step of the dry gum process.