the contrary, that an intermingling (in masses, it may be, but still complete), must take place above, and result in an almost indifferent diffusion of the vapour-laden air northwards and southwards with the returning counter-trades. The fact that the northern trades have a southerly motion as they enter the calm zone (passing here upwards), and vice versa, may lead to a slight preponderance of air (originally) from the northern hemisphere in the north-westerly counter-trade, and vice versa, but by no means (I should think), to anything approaching the systematic intercrossing imagined by Maury. On the other hand, the preponderance might lie the other way, owing to the effects of collision between the northern and southern trades-but without leading to the systematic return of northern air to the northern temperate zone, and of southern air to the southern temperate zone, conceived to take place by Sir J. Herschel.

One of the most remarkable results of observations made upon rain, has been the discovery that the amount of fall at any place diminishes largely as the rain-gauge is raised above the level of the ground. It is not very easy to explain this remarkable fact. The explanation offered by Kämtz is, that a falling drop carries with it the temperature of the upper regions of air, and condenses on its surface the aqueous vapour present throughout the lower strata of the atmosphere, as a decanter of cold water does when brought into a room. And of this explanation Professor Nichol remarks, that "it is not an hypothesis but a rigorous deduction, giving an account of all the facts as yet ascertained in connection with this subject." But unfortunately, the explanation, though it undoubtedly presents a vera causa, will not bear the test of "quantitative analysis." Sir John Herschel has gone through the simple calculation required to overthrow the theory, and points out, that if we allow to the cause the full value it can possibly have (a value far exceeding that which can probably be attributed to it) we obtain an effect only oneseventeenth part of what is wanted to account for the phenomenon. Sir John points out also that obliquity of fall cannot possibly affect the observed amount of rainfall, and he offers no hypothesis in explanation of the phenomenon, and remarks in conclusion, that "visible cloud rests on the soil at low altitudes above the sea-level but rarely; and from such clouds alone would it seem possible that so large an accession of rain could arise." He refers, however, in a note, to a paper read by Mr. Baxendeil to the Literary and Philosophical Society of Manchester on this subject, in which it is inferred that the only way of accounting for the phenomenon lies in the admission of the existence of water "not in the state of true vapour," but already deprived

of its latent caloric, though not affecting the transparency of the air, so that " a shallow stratum of the lower and comparatively clear atmosphere" may "supply as much rain as a densely-clouded and much deeper stratum in the higher regions." Baxendell mentions also the interesting fact, that the drops of water which drip from the upper part of the shaft increase to an extraordinary size in the descent to the bottom.

It appears to me that the well-known phenomenon of rain falling from a clear sky-a rain termed by the French sereinhas a suggestive bearing on the peculiarity we have been considering. It proves that water may exist, even in drops, in the atmosphere, without appreciably affecting its transparency. And though it may be an uncommon thing for rain to fall without appearing first in the upper regions of air-in the form of cloud, yet it by no means follows that during a shower rain might not be falling from the lower as well as from the upper air-strata, without the transparency of the lower strata being much or at all affected. I have noticed, always, that if the eye be directed steadily at the drops of heavily-falling rain, there will be seen flitting, as it were, among them minute specks, which are seen on a closer observation to be small particles of water. Now, it does not appear to me likely that these, or most of them, are produced by the collision of the falling drops-for the paths of two neighbouring drops must be parallel, since the drops are subjected to precisely the same set of influences.

I believe the phenomenon to be one worthy of more careful notice than it has received-in fact, I am not aware that it has been noticed at all. The motions of the particles are themselves interesting-seeming almost as independent of gravitation, wind-currents, or the like, as the motion of a flight of insects would be. It is hardly necessary to observe that if these particles show that rain is being generated in the lower as well as the upper strata of the air, all difficulty in explaining the results of Professor Phillips's observations, vanishes at

once.

THE GRAVE-MOUNDS OF DERBYSHIRE, AND
THEIR CONTENTS.

BY LLEWELLYNN JEWITT, F.S.A., ETC., ETC.

(Continued from page 266.)

THE ROMANO-BRITISH PERIOD.

As I have said earlier on, the greater part of the Grave-mounds of Derbyshire belong to the Celtic period; the intermediate number to the Anglo-Saxon, and by far the least of all to that now under notice, the Romano-British. There is, both in the lowlands of the county, and in the higher or mountainous districts of the Peak, abundant evidence of Roman occupation, and of the arts practised by that people, but very little knowledge indeed is to be gained there as to their funeral customs or their modes of sepulture. Of the living Roman and of his avocations, indications are not unfrequently brought to light by the burrowing miner, or by the surface-working agriculturist, but of the dead it is rarely indeed that any remains are exhumed.

In Derbyshire the Roman was, it would seem, more of a "bird of passage" (as well as, to some extent, a "bird of prey") than a settler, and the consequence is that no remains -or next to no remains-of villas or of settlements are found, and that where burial has taken place it has not unusually been in the same mound with those of an earlier period. The Ancient Briton raised the mounds over the remains of his own people, and his Roman subjugator, as occasion required, took possession of them, and therein laid his own dead. Thus the same barrow is sometimes found to contain, besides its primary Celtic interment, and others belonging to the same race, later deposits (nearer to the surface or to the side) of the RomanoBritish or of the Anglo-Saxon periods.

The Roman roads of Derbyshire were many in number, and some of them are of considerable importance. The principal line (as well, most probably, as some of the others) was formed on an old British way; while other roads were constructed by them for the convenience of working, and for greater facility in transporting the produce of, the mines, in which a profitable trade was carried on. The principal road, the Rykneld Street, entered the county from Staffordshire, and

passed over Egginton Heath to Derventio (Little Chester, now an outskirt of Derby); from thence to Pentrich (which is believed to have been a station), and so on to Lutudarum (Chesterfield), and forward into Yorkshire. From Little Chester several of the roads diverged, and other lines again traversed the Peak district, both in the neighbourhood of Buxton (supposed Aqua) and in other directions; whilst others again from the lead-producing districts centred in Chesterfield. The stations, and supposed stations, in Derbyshire, were at Little Chester, where a vast number of remains have been found; Chesterfield, where also coins, etc., have been discovered; Buxton, where Roman baths have been traced; Brough near Castleton; Melandra Castle, Parwich, and Pentrich. At each of these places remains of the period have been found. Roman coins, fibula, pottery, etc., have also been found in various parts of the county, and show that it must have been pretty fully traversed, and indeed occupied, by that people.

In the mining districts of the High Peak, Roman antiquities of one kind or another are being frequently turned up, and some of the lead mines, which exist and are worked at the present day, are proved to have been known to, and worked by, the Romans. This is, perhaps, more particularly the case in the neighbourhoods of Elton, Winster, Youlgreave, Matlock, etc., where even the names of some of the mines-such as the "Portway Mine," for instance-give evidence of their early origin. Pigs of lead of Roman manufacture have at different times been found in Derbyshire, some of which bear inscriptions referring to the station of Lutudarum (Chesterfield), to which I have already alluded. One of these inscriptions is :T. CL. TR. LVT. BR. EX. ARG., and another, ÎMP. CAES. HADRIANI. AVG. MET. LVT. The finding of these inscribed and other pigs of lead, the number of Roman roads which traversed the mining districts, and the number of coins and other articles which have from time to time been found about the mines, and in their neighbourhood, show that lead must have been produced to some considerable extent, and that a large number of people must have been engaged in the getting of the ore, and in smelting it.

When, in addition to the fact I have stated, that the Roman people did not make regular settlements in Derbyshire, we recal to mind the other fact, that they but seldom raised tumuli over their dead, or, in this country, placed any ostentatious monuments over their remains, the reason is obvious why so few of their sepulchral urns should have been found here, though, doubtless, many urns etc., still lie buried and will yet from time to time be unearthed. It is also necessary to re

member that the finding of a Roman coin in a barrow is no evidence of that barrow being raised by the Romans, or even of the person interred being of that race. "The Britons, looking upon these tumuli as a kind of sacred ground, continued, in many instances, to bury in the same barrow for ages after its first construction, and deposited with their dead in later times. the coins of their Roman masters, on the same principle as that which prompted them in earlier times to inter the rude weapons or ornaments of flint or bone."

The interments which have been discovered exhibit both burial by inhumation and by cremation. Of the former, examples have been brought to light at Little Chester in the course of excavations both for building purposes, and in the formation of the railway works. A skeleton of a man found there some years ago, lay full length on its back, the arms straight down by the sides. Iron rivets, which were found much corroded, lay near various parts of the body, and a thin stratum of ferruginous matter encased the skeleton at a little distance from the body and limbs. From these circumstances it is to be inferred that the deceased was interred in his armour. Other interments by inhumation have recently been discovered in the same neighbourhood, but without, in some instances, the ferruginous appearances. The remains of horses were found along with them. Interments by inhumation have also been found at Brough and at other stations, and, as later deposits, in Celtic barrows. Those where the bones have been found in situ, appear, like the one I have spoken of at Little Chester, to have been laid at full length on the back, the arms straight down by the sides. They appear in most instances to have been simply laid in a very shallow grave, but little below the surface of the already formed mound, and to have been then covered to no great thickness with earth. Where interment has been by cremation, the urn, sometimes covered with a small flat stone, containing the burnt bones, has been placed in a small hole dug in the earth, or in a Celtic barrow, and covered over. Not unfrequently domestic vessels have been placed with the cinerary urn, as will be hereafter described.

As the interments of the Romano-British period in Derbyshire are, as I have said, but few, so, naturally, the articles found with them are far from numerous. They embrace, however, pottery and glass, coins, fibulæ, armillæ, and other ornaments of bronze and iron, knives, spear-heads, combs, etc., etc. Of fibulæ, the three examples here engraved will convey a very tolerable idea. The first was found with a Roman interment in a Celtic barrow near Monsal Dale; the centre one was dug up with a quantity of human bones at Little Chester; and