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Excursion to the Medway valley from Maidstone to Aylesford
192
H. HICKS ON TilE GEOLOGY OF NORTH WALES.
Th e next overlying rocks, the LJand eilo series, have not so far proved of great importance in thi s ar ea, nor hav e they as yet been carefully separated here from the other groups. The Bala rocks of Snowdon ar e well known to all those who have ascended that mountain, and the int erstratifying volcanic bands and the intrusive rocks in this group will doubtl ess be described by Prof. Hughes in his report of the excur sion. Upper Silurian rocks are not likely to be t ouched during the Excursion, but may be met with, by th ose who wish to extend their researches, by visiting the neigh bourh ood of Conway, and partially also in Anglesey (according to Prof. Hughes.) The Old Red Sand stone occurs to th e south of Dulas Day in Anglesey, and the Carb oniferous series along the shores of Menai Strait, also at the north-east corner and in a line nearly across Anglesey in the direction of Malldraeth Marsh. (S ee Map) . Permian Rocks are stated also to occur at Malldraeth Marsh. The glacial deposits about Snowdon, &c., are of considerable interest, and marine sh ells ar e sta ted by Ramsay to have been found at heights of from 1,100 to 1,400 feet above the sea.
EXCURSION TO THE MEDWAY V ALLEY MAIDSTONE TO AYLESFORD. SATURDAY, JULY 14TH,
Director : -
J.
LOGAN
FROM:
1883.
LOBLEY,
F.G.S.
(Report by THE DIRE CTOR.)
As the Medway Vall ey, in the neighb ourhood of Maidstone, has been on several occasions visited by the Associat ion, and its geological structure described in the I Proceeding s,' '" it will be sufficient here to briefly record th e route taken and th e sections visited during this excursion. Previous to leaving the town of Maidstone, where the party assembled, a visit was paid to the Natural History Museum, which is so well placed in a fine old Man or House. Mammalian remains from the Post-Pliocene beds of Aylesford form an important portion of an extensive general geological collection, especially rich in the fossils of the local formations. Much time and great care have been given by th e Curator, Mr. Bartlett, to the preserve• Vol.iii,p. 88; Vol.iv,p.603; and Vol. vi,p. 392.
EXCURSION TO THE MEDWAY VALLEY.
193
tion of the numerous fish-bones, teeth, and tusks of Rhinoceros, Elephas, &c., which he has obtained from the old Medway gravels. A valuable collection of Kentish flint-implements also adds interest to this Museum. Crossing the Medway and ascending the high ground on the west of the valley, the party proceeded to the old Iguanodon Quarry of Bensted, now no longer worked. A large mound rising in the middle of the old excavation is the natural infilling of one of the great" pipes," so numerous in the Lower Greensand of this district, the surrounding Ragstone having been removed. Very good specimens of these pipes occur in Scrubbs Quarry, which the party next visited, and where the alternating beds of "Kentish Rag" and "Hassock," which form the Hythe Beds of the Lower Greensand, were well seen. The contents of the pipes have been worked for brick-making on the other side of the valley, where they are very large; but here the loamy material is, like the Hassock, unused, the quarries being worked simply for the valuable building-stone, the Kentish Rag. Though the great size of the pipes on the north-east of Maidstone would suggest a different origin, their occurrence of very various sizes in other places leaves no room for doubt that they are the result of the dissolving away of the calcareous rock by carbonated water, as has been the case with the well-known pipes in the chalk. Passing through some beautiful Kentish cherry-orchards and hop-gardens, the members made their way down the valley to Allington Castle on the river bank j but a passing visit was paid to another good specimen of a ragstone quarry, where the beds were found to be more fossiliferous, specimens of some of the common species of the Hythe Beds, as Enogyra sinuata and Trigonia alaformis, being readily obtained. The party having re-assembled in the interior of the interesting and picturesque ruins of Allington Castle, the old home of the W yatts, the Director recalled to the mind its ancient association with such names as Odo, Sir Henry Wyatt, the partisan of Henry VIII., Wolsey, Sir Thomas Wyatt, the poet, and that better-known Sir Thomas Wyatt, the leader of the rebellion against Queen Mary, who marched out of this Castle to capture London, but, failing in this, was beheaded on Tower Hill. The river was re-crossed and the valley traversed to Aylesford, where at the George Hotel the party dined.
194
EX CURSION TO THE MEDWAY VALLEY.
Subsequently the remarkabl e section near the village of AyJesford, where beds of old ri ver gravels repose on t he F olkestone Beds, was inspected. Thi s section is remarkable not only for the conspicuous different iation of the beds exposed, beds of L ower Cretaceous age supporting beds of P ost-Pliocene, but also for the rich Mammalian fauna here discovered. It is worthy of note that the only example of Elep has antiquus recorded from th e W ealden dist rict was found at this place. Thc valley-g ravels, twenty feet above the present bed of the river, indicate that the gorge of the Medway has been cut by a river flowing in the same direction as the present Medway, since they consist of flint pebbles int ermingled with W ealden pebbles, from the Upper Medway country, and t hese add support t o th e evidence derived from th e character of the pebbles of the othe r \Veald en rivers favouring the hypothesi s of the sub-ae rial denudat ion of the We ald. On leaving this int eresting section, the party was conducted to the Aylesford Pottery, where extensive excavations give very fine sect ions of the Gault here seen to underlie th e Upper Greensand, forming th e base of th e chalk escarpment. A gradually ascending walk of about a mile, over the Lower Chalk, crossing t he ancient Pil g rims'- Way, brought the members to K its-Coty House, occupying a conspicuous position on the hill-side, This far-famed cromlech consists of four large sarseu stones, t hree on end and one forming a top covering, and is supposed to be the burialplace of Catigrinus, who fell in an encounter with Horsa, fatal t o hot h, at th e battle of Aylesford, in A.D. 445. The principal featur es of th e porti on of the Medway Valley seen from this commanding spot were pointed out . A t a littl e higher level the Rochester and Maidstone road was followed, which runs along th e escarpment, and gradually descending southwards, crosses the L ower Chalk with " Grey W eth ers " on t he surface, the Upp er Greensand, th e Gault, th e F olkest one Beds, the Hyth e Beds, and the A therfield Clay, and reaches the W eald Clay at the town of Maidstone, where th ere is a triangular inlier of this format ion. The party t ook the train from Maidstone to return t o London.
H. HICKS ON TilE GEOLOGY OF NORTH WALES.
Th e next overlying rocks, the LJand eilo series, have not so far proved of great importance in thi s ar ea, nor hav e they as yet been carefully separated here from the other groups. The Bala rocks of Snowdon ar e well known to all those who have ascended that mountain, and the int erstratifying volcanic bands and the intrusive rocks in this group will doubtl ess be described by Prof. Hughes in his report of the excur sion. Upper Silurian rocks are not likely to be t ouched during the Excursion, but may be met with, by th ose who wish to extend their researches, by visiting the neigh bourh ood of Conway, and partially also in Anglesey (according to Prof. Hughes.) The Old Red Sand stone occurs to th e south of Dulas Day in Anglesey, and the Carb oniferous series along the shores of Menai Strait, also at the north-east corner and in a line nearly across Anglesey in the direction of Malldraeth Marsh. (S ee Map) . Permian Rocks are stated also to occur at Malldraeth Marsh. The glacial deposits about Snowdon, &c., are of considerable interest, and marine sh ells ar e sta ted by Ramsay to have been found at heights of from 1,100 to 1,400 feet above the sea.
EXCURSION TO THE MEDWAY V ALLEY MAIDSTONE TO AYLESFORD. SATURDAY, JULY 14TH,
Director : -
J.
LOGAN
FROM:
1883.
LOBLEY,
F.G.S.
(Report by THE DIRE CTOR.)
As the Medway Vall ey, in the neighb ourhood of Maidstone, has been on several occasions visited by the Associat ion, and its geological structure described in the I Proceeding s,' '" it will be sufficient here to briefly record th e route taken and th e sections visited during this excursion. Previous to leaving the town of Maidstone, where the party assembled, a visit was paid to the Natural History Museum, which is so well placed in a fine old Man or House. Mammalian remains from the Post-Pliocene beds of Aylesford form an important portion of an extensive general geological collection, especially rich in the fossils of the local formations. Much time and great care have been given by th e Curator, Mr. Bartlett, to the preserve• Vol.iii,p. 88; Vol.iv,p.603; and Vol. vi,p. 392.
EXCURSION TO THE MEDWAY VALLEY.
193
tion of the numerous fish-bones, teeth, and tusks of Rhinoceros, Elephas, &c., which he has obtained from the old Medway gravels. A valuable collection of Kentish flint-implements also adds interest to this Museum. Crossing the Medway and ascending the high ground on the west of the valley, the party proceeded to the old Iguanodon Quarry of Bensted, now no longer worked. A large mound rising in the middle of the old excavation is the natural infilling of one of the great" pipes," so numerous in the Lower Greensand of this district, the surrounding Ragstone having been removed. Very good specimens of these pipes occur in Scrubbs Quarry, which the party next visited, and where the alternating beds of "Kentish Rag" and "Hassock," which form the Hythe Beds of the Lower Greensand, were well seen. The contents of the pipes have been worked for brick-making on the other side of the valley, where they are very large; but here the loamy material is, like the Hassock, unused, the quarries being worked simply for the valuable building-stone, the Kentish Rag. Though the great size of the pipes on the north-east of Maidstone would suggest a different origin, their occurrence of very various sizes in other places leaves no room for doubt that they are the result of the dissolving away of the calcareous rock by carbonated water, as has been the case with the well-known pipes in the chalk. Passing through some beautiful Kentish cherry-orchards and hop-gardens, the members made their way down the valley to Allington Castle on the river bank j but a passing visit was paid to another good specimen of a ragstone quarry, where the beds were found to be more fossiliferous, specimens of some of the common species of the Hythe Beds, as Enogyra sinuata and Trigonia alaformis, being readily obtained. The party having re-assembled in the interior of the interesting and picturesque ruins of Allington Castle, the old home of the W yatts, the Director recalled to the mind its ancient association with such names as Odo, Sir Henry Wyatt, the partisan of Henry VIII., Wolsey, Sir Thomas Wyatt, the poet, and that better-known Sir Thomas Wyatt, the leader of the rebellion against Queen Mary, who marched out of this Castle to capture London, but, failing in this, was beheaded on Tower Hill. The river was re-crossed and the valley traversed to Aylesford, where at the George Hotel the party dined.
194
EX CURSION TO THE MEDWAY VALLEY.
Subsequently the remarkabl e section near the village of AyJesford, where beds of old ri ver gravels repose on t he F olkestone Beds, was inspected. Thi s section is remarkable not only for the conspicuous different iation of the beds exposed, beds of L ower Cretaceous age supporting beds of P ost-Pliocene, but also for the rich Mammalian fauna here discovered. It is worthy of note that the only example of Elep has antiquus recorded from th e W ealden dist rict was found at this place. Thc valley-g ravels, twenty feet above the present bed of the river, indicate that the gorge of the Medway has been cut by a river flowing in the same direction as the present Medway, since they consist of flint pebbles int ermingled with W ealden pebbles, from the Upper Medway country, and t hese add support t o th e evidence derived from th e character of the pebbles of the othe r \Veald en rivers favouring the hypothesi s of the sub-ae rial denudat ion of the We ald. On leaving this int eresting section, the party was conducted to the Aylesford Pottery, where extensive excavations give very fine sect ions of the Gault here seen to underlie th e Upper Greensand, forming th e base of th e chalk escarpment. A gradually ascending walk of about a mile, over the Lower Chalk, crossing t he ancient Pil g rims'- Way, brought the members to K its-Coty House, occupying a conspicuous position on the hill-side, This far-famed cromlech consists of four large sarseu stones, t hree on end and one forming a top covering, and is supposed to be the burialplace of Catigrinus, who fell in an encounter with Horsa, fatal t o hot h, at th e battle of Aylesford, in A.D. 445. The principal featur es of th e porti on of the Medway Valley seen from this commanding spot were pointed out . A t a littl e higher level the Rochester and Maidstone road was followed, which runs along th e escarpment, and gradually descending southwards, crosses the L ower Chalk with " Grey W eth ers " on t he surface, the Upp er Greensand, th e Gault, th e F olkest one Beds, the Hyth e Beds, and the A therfield Clay, and reaches the W eald Clay at the town of Maidstone, where th ere is a triangular inlier of this format ion. The party t ook the train from Maidstone to return t o London.