The Lime Kilns about 1910 [Z1306/127]
The chalk of the downland around Dunstable and Totternhoe was formed in the period when the dinosaurs ruled the earth, which ended with their extinction - the Cretaceous Period, dating from 145.5 million years ago to 65.5 million years ago. During this vast period of time microscopic algae multiplied in warm, shallow seas. On death they fell to the sea bed and, together with clays washed from the land still above water, built up the thick layers of chalk. As the seas rose higher the harder limestone that rest on this bed was deposited - again mostly from the skeletons of minute algae.
Chalk dug out from Totternhoe Chalk Pit (now abandoned and a Site of Special Scientific Interest since 1990 due to its increasingly rare chalk downland habitat for flora and fauna) was heated to around 1000 degrees centigrade to leave calcium oxide, known as quicklime. This was added to water in a process known as slaking and a violent chemical reaction took place to produce lime mortar for bonding stone together or the addition of more water gave limewash used to coat the interior and exterior of buildings. Chalk with a higher content of clay made cement when added to water during the slaking process.
There is still a limeworks at Totternhoe at the time of writing  on a site since probably in use since the 17th century. Chalk is now brought to the plant from outside the parish, however. The Totternhoe Lime, Stone and Cement Company Limited ran the works from about 1898, leasing it from the Ashridge Estate.
The Totternhoe Estate (part of the Ashridge Estate) was put up for sale by Lord of the Manor of Totternhoe, Earl Brownlow in 1916 [Z513/22]. Lot 23 was "the well-known valuable property" the Totternhoe Lime Stone and Cement Works, comprising a quarry, kilns, manager's house and buildings and several meadows and fields of arable land all comprising 64 acres, 1 rood, 37 poles and let to the Totternhoe Lime Stone & Cement Company Limited for £236/16/6 per annum.
The property is described thus: "THE LIMESTONE QUARRY contains valuable Beds of Building Stone and THE BUILDINGS include 16 Kilns (average capacity 27 tons), Grinding House, Engine Shed and Office. Engine Shed, Smithy, Office and Weighbridge by Pooley & Son, and Water Tank on brick piers. NOTE - The foregoing buildings were erected by the Lessees".
"THE MANAGER'S HOUSE is substantially built of brick, with tiled roof, and contains: - On the GROUND FLOOR, Porch, Sitting Room, Living Room, Wash-house with copper, and Scullery with sink and copper; on the FIRST FLOOR, Four Bedrooms. Excellent Garden in the front, and at the rear a Range of Buildings containing Stabling for six, Loose Box, Chaff House and Loft over, Carpenter's Shop and Loft over. Barn and Loft and lean-to Engine-Shed, the latter erected by the Lessees. On the opposite side of the road is a 3-bay open Shed, Cowsheds and several Piggeries, and Yard with Well". The Totternhoe Lime, Stone and cement Company changed its name to the Totternhoe Lime and Stone Company Limited about 1924.
In 1936 Totternhoe Lime and Stone Company Limited began working with the Rugby Portland Cement Company Limited. Industrial Archaeology in Bedfordshire produced by Bedfordshire County Council in 1967 [PL/Pu/AC3/1] has this to say of Totternhoe lime kilns: Totternhoe Lime and Stone Company. There were originally twenty-eight pairs of kilns used for chalk burning of which only three now remain. One of these is to be maintained in its present condition. Mr. A. R. Bates, owner of the company, claims that these kilns are about four or five hundred years old. The present kilns will not, however, date back so far since both the interior and exterior brickwork will have been continually replaced during that period. According to the yard foreman the flare kilns were last used commercially in 1954, having been superseded by the more economic shaft kilns.
The yard foreman, Mr. Blew, described the chalk firing process as follows: "The kiln is filled with about sixty-five tons of chalk and three tons of coke, introduced in alternate layers. It was fired through fire holes in the bottom, coke being used for the first day and coal for the next two days. After burning en days, an average of twenty-five tons of quicklime was produced. These lumps of lime reduced to a fine powder after contact with water".
By 1977 two of the flare kilns mentioned survived. The last of these were demolished in 2006.