There are many localities around London which possess features of interest to the geologist, that can be reached and examined on a single day. Such a one is the pretty little town of Bromley, in Kent, with a population of 4,000 souls, at a distance of ten miles from London Bridge, and now within easy reach by the Mid Kent Railway, only just opened. A mile to the north-east of Bromley is Sunderidge Park, in which is to be seen a section of the well-known oyster-conglomerato rock, in a large pit which, together with the accompanying shingle, has been quarried for various purposes for many years. This spot is noticed by Dr. Mantell in his charming volumes, as one of the most interesting localities he was acquainted with. At and around Bromley is an area of some extent, formed by the Lower London Tertiaries; a small patch of chalk, however, crops out to the east of the town, in which are some ancient quarries. One of these possesses some interest from being underground, and containing, as I was informed, several intricate windings.

The London clay, with the underlying plastic or Woolwich clays, and Tnanet sands, constitute the lower division of the Eocene strata of the Tertiary group of rocks. The London clay extends over several counties of England, constituting a large part of the soil of Essex, nearly the whole of Middlesex, and portions of Berkshire, Surrey, and Kent.