Saturday, 16th August, Mussel Camp. Started at nine o'clock. Another of my horses very ill; I think that many of them must have eaten some poisonous plant on the Roper and its tributaries; I never saw horses fall away so rapidly before. The worst are those that have been in good condition throughout the journey, and the work they have been doing since I commenced my return journey any horses ought to have done with ease. I have never travelled more than eight hours a day, and frequently not more than six hours. In a day or two they fall away to perfect skeletons, are quite stupid, and hardly able to walk. I am glad that I am now quit of the Roper, and hope that I shall have no more of them taken ill. If I can only get the weak ones beyond Newcastle Water, where I expect to get some new grass for them (from the June and July rains), they would soon recover. My old horses are all looking well, although they have had to carry the heaviest loads throughout the journey. I should have been in a sad way without them--they are my mainstay. Arrived at the Rock Camp, River Strangways, at two o'clock without having to leave any more. I feel a little better to-day, but the motion of the horse has been very severe throughout the journey. The water at this camp is drying up very rapidly: it is reduced three feet in depth since we left, and I am very much afraid it will be all gone in Purdie Ponds--if such is the case, I shall lose all the weak horses. Wind in strong puffs, variable.