October 3rd, for instance, I find that we were crossing them at a rate of ten in forty minutes.  This gives a result of 105 ridges to be negotiated in a day’s march of seven hours.  Riding was almost impossible in such country as this, for all our energies were required to urge on the poor camels.  All through, we adhered to the same plan as before, viz., doing our day’s march without a halt (excepting of course the numerous stoppages entailed by broken nose-lines, the disarrangement of a pack, or the collapse of a camel), having no food or water from daylight until camping-time.  This, without our previous training, would have been an almost impossible task, for each ridge had to be climbed—­there was no going round them or picking out a low place, no tacking up the slope—­straight ahead, up one side, near the top a wrench and a snap, down goes a camel, away go the nose-lines, a blow for the first and a knot for the second, over the crest and down, then a few paces of flat going, then up again and down again, and so on day after day.  The heat was excessive—­practically there was no shade.

The difficulties of our journey were increased by the necessity of crossing the ridges almost at right angles.  With almost heart-breaking regularity they kept their general trend of E. by N. and W. by S., causing us from our Northerly course to travel day after day against the grain of the country.  An Easterly or Westerly course would have been infinitely less laborious, as in that case we could have travelled along the bottom of the trough between two ridges for a great distance before having to cross over any.  The troughs and waves seem to be corrugations in the surface of greater undulations; for during a day’s march or so, on reaching the top of one ridge, our view forwards was limited to the next ridge, until a certain point was reached, from which we could see in either direction; and from this point onwards the ridges sank before us for a nearly equal distance, and then again they rose, each ridge higher than the last.  Words can give no conception of the ghastly desolation and hopeless dreariness of the scene which meets one’s eyes from the crest of a high ridge.  The barren appearance of the sand is only intensified by the few sickly and shrunken gums that are dotted over it.  In the troughs occasional clumps of shrubs, or scrubs, [e.g., Mulga (acacia ANAEURA), grevillea, hakea, ti-tree (Melaleuca) and in the northern portion desert oaks (Casuarina DESCAINEANA)] or small trees are met with, and everywhere are scattered tussocks of spinifex.  True it is, though, that even this poverty-stricken plant has its uses, for it serves to bind the sand and keep the ridges, for the most part, compact.  Where spinifex does not grow, for instance on the tops of the ridges, one realises how impossible a task it would be to travel for long over banks of loose sand.