may find its way down the narrow valleys from the Cordilleras to the west.

It is the garua, or thick winter mist of the coast, that nourishes the seeds transported to the flower spots. First in the progress of organic life is a spare pasture; upon this a few wild huanaco and vicuña feed, having migrated from the Cordilleras. A stray fox may sometimes be met with, but what this animal finds to eat I cannot tell. The condor is seen to whirl about majestically, and a little slate-coloured bird may be heard to chirrup at times.

Whilst exploring, I came upon some of the party who had got into a growth of the small blue and white lilies. They were in great glee, and I could hear them joyfully exclaim, as I was botanically occupied, "Look, how pretty these flowers are; how beautiful, see, see! Why not remain here for ever, build a house, and always have a garden?" Yes, these periodical and stunted flower spots in the desert seemed then to my friends ever-blooming glades, and sylvan groves.

I collected specimens of the pasture, lilies, and oxalis; in all about twenty different species of plants, one of which, I think, must have been a Solanum, or member of the potato family,* and there was one plant I tried to persuade myself was a shrub. I came upon two or three species of small cacti, and then fell in with what I took for the gigantic cactus, with a yellow flower. Some of these were thirty to forty feet high, the girth at the base being ten to fifteen feet. I think it is the same species I have seen in abundance on the lower portions of the Cordilleras, where it is so tough as to be cut into narrow planks. These cacti are in comparative abundance, and on some occasions have been used as fuel at Iquique. I found the bright green leaf of one plant rolled up in such a manner as to enable it to hold a portion of water. This was handy, I thought, for the little slate-coloured birds to drink.

I found on the cacti the following Bulimi, named, I believe, by Mr. Cumming: Succinea Broderipii, Bulimus virgulatus, B. erosus, and at their roots little heaps of their dead shells. Laden with specimens of the plants, bulimi, and pieces of rock, I returned to our camp, where an excellent repast was set out, including a good salad made from the Vinagrillo, or Oxalis Acetosella. Here we remained for some time discussing our repast in this mountain solitude.

Of the flowers which had been collected, some were made into bouquets, others placed round our hats; even the headgear of the donkeys came in for a share of floral ornamentation.

We now commenced our journey back to Iquique, bidding adieu to the Valley of the Lilies. We ascended to the pass of * This collection I have presented to the Linnean Society.

Guantaca, from whence we had a glorious view of the Pacific and its iron-bound shores. Rapidly descending the mountain range, at times our animals had to slide down through the deep sandy track; arriving at the bottom, we trotted briskly over the plain to Iquique, which we reached whilst the vesper bell was ringing for the "Oracion," when all good Roman Catholics kneel to say the evening prayer.

We were now a goodly party, but got them all fairly accommodated. For some days afterwards our mountain friends enjoyed sea-bathing, fishing, paddling about on balsas, trips to the island, formerly covered with guano, and hunting for shells.

At this juncture a good friend to the poorer people of the whole coasts, Captain Bowers, came into the bay with his ship, the "Catalina." He did not require any pressing to give a dinner and dance on board his vessel, which was heartily enjoyed by all.

A few days afterwards our Santa Rosa and Huantajaya friends returned to their mountain homes, the abodes of the silver-fabricating gnomes of Tarapacá.

OBSERVATION OF BOLIDES.

BY ALEXANDER S. HERSCHEL, B.A.

THE description of a large meteor's passage through the air has been a narrative homely and familiar to all since the ingenuity of man first combined the elements of earth and air and fire, to direct the flight of rockets and to please the eye with the gay discharges and the flashes and explosions of fireballs. Yet the spectacle is grand and awful when we revolve the real wonders of the sight. If it is seen by day, no bird is so high, no balloon, nor even a cloud; mountains and valleys are undistinguishable to this visitor as it swiftly approaches the dangerous circle of our globe. If seen at night moving beneath the stars, it is nearer to those than the whole height of our dull but lofty atmosphere!

Suppose it to be a small shooting-star only that is seen. Its distance and its trajectory are as great as those of a meteor. Philosophers are not yet agreed upon the true nature of these apparitions, but it appears not improbable that the shootingstar is an exceedingly small paring of metallic iron, or a grain of sand, piercing at twenty to thirty miles a second, the extreme fluid coverings of the earth. The brightest meteor, it is equally probable, may be no larger than a schoolboy's marble, or a

hazelnut or walnut! Such a fragment may yet suffice, with great velocity, to strike the air with rolling thunder, just as the slender thong of a whiplash may be made, with velocity enough, to produce an astonishing report. As the floating fibres of the whipcord mark the spot at which the lash was drawn with detonation through the air, so these unearthly projectiles leave luminous clouds of unknown nature floating on the course to mark their track, and in the cause of this remarkable phosphorescence is undoubtedly to be sought the origin of the vivid light that the slender fragments are able to elicit from the air. By the blow of their intrusion through different regions of density, aided by the disruptive, liquefying, and calcining actions of the heat which probably accompanies the light, their slight substance is crushed and scattered or exhausted, the velocity, quickly yielding to resistance, is destroyed, and their subsequent descent to the earth in a few extremely small fragments is no longer matter of perception. Some larger bodies, however, occasionally encounter the earth's globe, and, piercing the fluid envelopes, penetrate, with unexhausted velocity, to the ground; but their occurrence is singalar and rare. Such aerolites, or aerosiderites, as they are called (masses of stone or iron fallen from the air), are preserved in considerable numbers in our national museums, where they form collections yearly increasing in interest and extent. The stones possess a great resemblance or likeness of character among themselves. Scattered through the fragment of a greyish-looking sandstone are seen glittering particles, like filings, of metallic iron alloyed with nickel, bright particles of iron pyrites, or iron combined with sulphur, and particles of olivin, a yellow, gem-like crystal, or of felspar, the crystalline component of granite. Frequently oolitic or seed-like grains of all of these mixed substances together abound throughout the structure. The fragment is entirely clothed with a thin, black, polished or enamelled crust. The last is the same glass or slag to which the mineral is fused before the blowpipe, and on certain specimens it may be seen raised in wave-like lines, as if rippled in the molten condition by the force of a powerful wind. When on any side the crust is wanting, the fracture has, in some remarkable instances, been exactly covered by the similarly exposed faces of smaller stones, fallen at the same time many miles from the place of the principal descent. These accumulated fragments of the several falls give from a few pounds to many hundred weight, as the weight of foreign matter occasionally descending to the earth. The aerosiderites are of much greater weight, but of various sizes, little altered by their passage through the air. Like rude settings of valuable gems, the clear crystals of olivin are seen bedded in their sponge-like cavities. The metal contains invariably a portion of nickel in

alloy, and its fibres are found by section and etching to have a constant crystalline structure. The character of these minerals, and the circumstances of their arrival, places their extratelluric origin apparently beyond a doubt. Professor Quetelet has, however, most recently doubted the existence of an unbroken analogy between these bodies and the smallest shooting-stars. Such an analogy can only be traced in the fugitive or ephemeral features of their apparition, and simultaneous observations at distant places of one and the same fugitive flight are indispensable to the study; but of the rarer aerolitic falls no precise observations of the kind are found; shooting-stars, and the associated class of bolides (fireballs or large meteors) and detonating meteors, have alone yielded trustworthy results to observation. The periodic recurrence of the first, in showers, renders the tribe of shooting-stars an old subject for concerted observation, and bolides no less would seem to appear in groups, but not expectedly. Unless it be that the brilliance of a single individual elicits by discussion the notices of others no less brilliant than itself, instances may be cited to show that the recurrence of this phenomenon twice upon the same evening is more probable than that a brilliant meteor should appear alone and singly in a day. Until a physical connection can be pointed out by reason of which a group of shooting-stars should have one, or the least, dimension in common, such a group of bolides a second dimension in common, and lastly by which the aerolites, perhaps too far apart to show themselves in groups, occupy a series of superior dimensions, three classes of phenomena apparently distinct present no hypothesis whereby they may be collected under a single head. Some recommendations which follow for the observation of large meteors, may possess points of interest for those who are not habitual gazers upon the heavenly vault.

When a large meteor attracts the gaze of a fortunate beholder, let him attend some minutes for the occurrence of a report. Throughout the flight of the meteor he may compare in numbers the length of the head with its width, and certain peculiarities of figure, light, and colour common to meteors will correctly impress themselves upon him as they arise, and afford ground for future remarks. Immediately on the meteor's disappearance the points of appearance and disappearance of its course should be compared with surrounding objects. All objects, whether the angles and roofs of houses or the boughs of trees, should be pressed into this service, to avoid the uncertainty which quickly arises when the light has disappeared. On a starlight night, if the constellations can be recognized, no better course can be pursued than to align or triangulate the points of apparition and extinction with the best-known neighbouring constellations; but, in default of these, the places of appearance

and disappearance should be marked with deliberation by surrounding objects, and a visit to the spot may be made at some future time for measurement. Sentences, numerals, or the alphabet should be repeated in estimation of the meteor's duration or of the interval elapsed to the occurrence of a report. The first of these estimations, leading to a knowledge of the meteor's velocity, is of especial value to the theory of their origin. To measure from landmarks the course of the flight, there should be cut from stiff cardboard an altitude card (six inches by three) of the following pattern :

A B C D is an oblong card, twice as long as broad, one corner of which is cut away by the quadrant c of a circle, about the centre E, graduated with a protractor to ninety degrees of arc from the transverse to the longitudinal direction of the card, as shown by the figure. A plummet line, with small weight attached (as shown at G), is fastened at the centre, and hangs freely over the face of the graduations while the card is in use. A series of transverse incisions F F F ... divide the back of the card into ribs, which admit the point of a straight rod or cane inserted between them to the whole length of the card in the direction of the arrow. This instrument has every

*The alphabet may be repeated distinctly fifteen times in a minute, and in small intervals of time the sixth part of a second becomes by its aid a quantity sufficiently easy to observe.

VOL. III.-NO. III.

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