Molasses - dry vs. wet
The American English term 'molasses' translates to 'dark treacle' in British English. Dried molasses, at least that which I am familiar with, is sulphered blackstrap molasses (the darkest, most bitter variety) and typically used as animal feed or as a soil amendment.

If you can't find dark treacle and your recipe calls for white sugar substitute golden syrup (similar to a very light molasses) or honey for the molasses and substitute brown sugar (which is a mixture of white refined sugar and molasses) for white sugar to up the molasses flavor with dark brown sugar preferred as it has more molasses added. Pack the brown sugar and substitute 1:1 on a volumetric basis.