I'm planning to make a cob bench under a protected porch. I have some clay soil, but just acquired a whole mess of used bricks. Does anyone know if it would it be possible to make the bench with mostly brick and then do a top coat with cob to found it out and at some artistic elements? If so, should I use an earthen mortar between each brick or do you think I could dry stack a layer and then put a layer of cob mortar across the whole layer and keep repeating? Since its protected and doesn't get much moisture would it still be good to put a layer of pea gravel in the bottom for drainage? Any suggestions or advice would be much appreciated.