Journal of a tour in Marocco and the Great Atlas / by Joseph Dalton Hooker, K.C.S.I., C.B., Pres. R.S., director of the Royal Gardens, Kew, etc. and John Ball, F.R.S., M.R.I.A., etc. ; with an appendix including a sketch of the geology of Marocco, by George Maw, F.L.S., F.G.S