A singular and interesting atmospheric phenomenon occurred at Hountop. Between seven and eight o’clock in the evening of the 24th of June, when reading by the side of my bivouac fire, I was suddenly startled by the whole atmosphere becoming brilliantly, nay, almost painfully illuminated. On turning to the quarter of the heavens whence this radiance proceeded, I discovered a most magnificent shooting star, passing slowly in an oblique direction through space, with an immense tail attached to it, and emitting sparks of dazzling light. The fire by which I sat was exceedingly bright, and the moon clear and brilliant, yet they were both totally eclipsed by this immense body of light. Its great beauty and brilliancy might perhaps be best realized by saying that it was like a star of the second or third order when compared to the moon at full.
After a time, the pasturage being nearly exhausted in the neighborhood of the Hountop, we removed our camp a few miles southward to another periodical river called the Aamhoup. During our stay here we observed some very striking and singular horizontal refractions of the air. Once I saw an ostrich walking on the horizon line, while its double—clear and well defined—appeared immediately above it. Both the ostrich and its double, moreover, were divided into three different portions by as many different strata of air.
Again: regularly every morning, for nearly a month, the projecting ledge of a rock was converted into the semblance of a splendid and embattled castle. As the atmosphere became uniformly heated, the mirage melted away into a soft, watery haze.
In usual refractions the inverted image of an object generally appears above the object itself, but occasionally the effect is reversed. Captain Scoresby, the well-known Arctic navigator, once by these means discovered his father’s vessel the day before it actually came in sight.
It has long puzzled the learned to account for the mirage. I believe, however, it is now pretty well known to arise from the unequal density and temperature of the lower strata of air.
The abundance of good water and pasturage had enabled our cattle to get into excellent condition; and as the season was now far advanced, and I was sufficiently well to travel, we deemed it necessary to move slowly on toward the Cape Colony. Accordingly, on the 9th of July we left our camp on the Aamhoup, a place where we had experienced both misery and happiness.
Our course lay along and at the foot of a very picturesque range of table hills, averaging about one thousand feet in height. To the westward were also mountains of a similar nature, but less regular. They were of the trap formation, and consisted chiefly of limestone.
Water continued for a time to be tolerably abundant, but pasturage began soon to fail us. Two causes were to be assigned for this, namely, the devastation of the locusts, and the inferior quality of the soil, which became stony, interspersed here and there with ridges of sand.
Among the latter we encountered herds of gemsboks, and troops of lions following on their scent. The mere sight of the tracks of the latter frightened a friend with whom I was traveling almost out of his wits. We were riding in advance of our cattle at the time, and it was with difficulty that I could prevent him from returning with precipitation.
On the 4th of August we arrived in the neighborhood of another Rhenish missionary station, called Bethany. Here we met with the ebony-tree, of which I had only before seen a few stragglers in the Swakop River, near the Usab gorge. Hence on to the Orange River this tree became more or less abundant, but it was stunted and gnarled. Our bivouac fires usually consisted of its wood.