John Allen Howe

John Allen Howe OBE started his career as a field geologist, first at the Royal College of Science in London, and then with the Geological Survey of Great Britain. However, his preference was for applied geology rather than fundamental research. In 1902 he became curator and librarian of the Museum of Practical Geology, a post he held until 1920 when he was appointed assistant to the director of the Geological Survey, retiring in 1931. It was with the practical aspects of geology that he became most well known and he was particularly involved in the work of the Institution of Mining and Metallurgy, of which he was president from 1942 to 1944 and who awarded him honorary membership in 1949. Even though his later interests tended towards minerals exploration and mining, it is his earliest book, The Geology of Building Stones, for which he is now probably best known.

Although it is perhaps the medieval cathedrals and castles, together with the stately country houses of the sixteenth and seventeenth centuries, which first come to mind when considering stone buildings, stone was still a major material for both prestigious and domestic projects at the start of the twentieth century. The nineteenth century had been a period of extensive stone building. Projects from the period ranged from Barry’s Palace of Westminster and his Royal Institution in Manchester, both built in the first half of the century, to the great Town Halls of Manchester and other northern cities built in the second half. Even the first example of a ‘New Town’ in Britain, Saltaire in Yorkshire, had been built of stone. By the time Howe joined the Geological Survey, brick and terracotta were being extensively used in addition to stone. Even so, architects such as Sir Edwin Landseer Lutyens, W. R. Lethaby and R. N. Shaw were still using stone. J. L. Pearson’s cathedral at Truro, built of Bath stone and local Mabe granite, was being completed by his son, and work was about to start on the new Anglican Cathedral of Liverpool, designed by Sir Giles Gilbert Scott and to be built in local sandstone. The use of local stone was still relatively common. For example, Lutyens used Bargate stone from the Guildford–Godalming area for many of his country houses in that part of the country.

Despite this extensive use of stone, there was no reference work available which provided information on the tremendous range of building stones which had been used in Britain and, perhaps more importantly, were still being produced. The appendices B and C provided by Howe, which list the larger operating sandstone and limestone quarries, give some idea of the scale of the industry at the start of the twentieth century. The first comprehensive study on British building stones, Hull’s A Treatise on the Building and Ornamental Stones of Great Britain and Foreign Countries had been published in 1872. However, this earlier work is a much more general description of a range of foreign, as well as British, building stones. Hull puts great emphasis on granites and marbles but, as the science of petrography was in its infancy, H. C. Sorby only having made his first petrographic thin section in 1849, the terminology used is now rather antiquated and the book is of little interest today, except in a historical context. Some practical information on the better known stones available at the start of the twentieth century could be found in books such as William Purchase’s Practical Masonry, the fifth edition of which, published in 1904, contained a new brief section on the nature of building stones, together with sections detailing some of the stones available and their prices. A work bringing together what was known about British building stones would, therefore, be a valuable aid to those wishing to use this traditional resource.

As the curator and librarian at the Geological Survey, Howe was in a position to bring together all the information then available, not only from the field mapping of the Survey, but also from the building stone collection housed at the museum. Being concerned with the application of geology, he realised that the information on building stone was required by those involved in using the material. As a result, and as he points out in his preface, the book is designed to fulfil the ‘requirements of students of architecture’. Containing a wealth of geological and other scientific and technical data, the book is nevertheless still eminently readable by those with little knowledge of geology. Furthermore, it relates the various stones to actual buildings. This is not only valuable in the historical context, but also allows the stone to be seen in use. As all those who have been involved with building stones will attest, there can be major differences between a stone straight from the quarry and the same material after a period of time in a building. In addition, comments on locations where stone has been used, particularly the rarer ones, can be of great help to conservators and architects when attempting to identify stone in a building.

The effect of pollution, frost and organic growth on the breakdown of stone had been recognised in the nineteenth century, and academic research had been carried out on various aspects of this. In 1861 a Select Committee had been established to examine ‘The causes of decay in the New Palace at Westminster’, some of the stone in the new building having lasted no more than about ten years. This report appears to have had few if any practical results. Geologists and other scientists were aware of the various factors which could destroy stone and eventually produce soil. The publication of Howe’s book was, however, the first time the subject had ever been brought in any detail to the attention of the users of stone. For the first time architects and others were shown that stone is subject to all sorts of harmful mechanisms, from lichens, to frost, to heat, to pollution, and even to polishing ‘where loafers congregate and sun themselves’. Despite the fact that this study of stone decay was to be superseded twenty two years later by Schaffer’s seminal work on The Weathering of Natural Building Stones, the chapter is still a good introduction to the subject. The same can be said for the section on stone testing. In fact, his views on testing were many years ahead of their time. He considers microscopic examination ‘affords a most convenient and reliable means for the investigation of the character of a building stone’. There is also a plea for ‘some scheme of Standard Tests, and some organization of authority for carrying out tests regularly and quickly’. Almost a century after these comments were written, Britain is now starting to obtain its first standard tests for building stone, in the form of European Standards, including one for petrographic description!

Although still a leading work of reference, some of the geological nomenclature is a little dated. Advances in geology have resulted in some changes to stratigraphic names. For example the Carboniferous strata originally termed the Millstone Grit by Whitehouse in 1778 and the Coal Measures, a term proposed by Farey in 1811, are now both part of the Silesian Subsystem. The Lower Freestone, a traditional building limestone within the Middle Jurassic, has now become the Cleeve Cloud Member of the Birdlip Limestone Formation. However, since geological maps and memoirs are updated relatively infrequently, the traditional names still occur in much of the more recent literature. Where the new terminologies are used, the traditional names are invariably provided, in order that reference can be made to earlier studies. In the case of Howe’s discussion of the decay of building stone, although his analysis is sound, recent advances have improved our understanding of the decay mechanisms. It is also pertinent to note that there appear to be occasional errors in the naming of locations from which stone was obtained. Those which have been reported are listed below:

Page 154 Cullington should read Cubbington
Page 218 Clipsham is in Rutland, not near Charlbury in Oxfordshire
Page 316 Stockholm is believed to be Skokholm (or Skokeholme) Island off the
              Pembroke coast (information supplied by Mr Terry Hughes)
Page 318 Chacombe is in Northamptonshire, not in Wiltshire. This incorrect location
              is actually taken from an earlier reference (information supplied by Mr Terry
              Hughes)
Page 323 Atford in Wiltshire, or Atforde as it is shown on early maps, is now known
              as Atworth
Page 324 Lumdon is almost certainly Swindon, this being the only place where the
              Purbeck is known to have been quarried in the area (information supplied
              by Mr Terry Hughes)

These occasional errors are possibly attributable to the poor handwriting of some field geologists, whose field notes Howe probably used when compiling the book! It is perhaps unfortunate that Howe did not include maps showing the location of the various stone types. However, the British Geological Survey’s Building Stone Resources Map of the United Kingdom, published in 2001, despite not showing all the locations mentioned by Howe, may well prove to be a useful companion to his book.

Despite having been written nearly a century ago, the book still remains an extremely important source of information on building stones. Conservators, restorers, architects and civil engineers, will welcome this facsimile reprint as the starting point for any investigation involving the identification of stone in old or historic buildings. It will not necessarily provide instant answers to the type and source of a stone used in a specific building or area, but it will certainly point the investigator in the right direction.

David Jefferson B.Sc.(Hons), Ph.D., C.Eng., F.G.S., F.I.Q., M.I.M.M.

David Jefferson spent twenty years working all over the world as a geologist with Blue Circle Industries before starting his own consultancy in 1985. He now specialises in mineral-based materials such as building stones, lime and cement, which are related to construction. He is currently geological consultant to the Building Conservation and Research Team of English Heritage, his work including identifying building stones, locating replacement stone, advising on the possible effects of surface treatments and cleaning. He has also worked on a number of National Trust properties and advises a wide range of architectural clients, as well as owners of building stone quarries.