Yes, you have guessed it - FULLER’S EARTH. Used by the Greeks and the Romans as a primitive sort of soap, used as a coating for Growmore fertilizer and at the very bottom of the scale – for cat litter.

To be fair, despite its unattractive appearance, it is deserving of greater distinction than that. Perhaps that is why it is frequently referred to as montmorillonite or bentonite. However the Romans called the laundries attached to their settlements FULLONICA, hence the Latin TERRA FULLONIA or Fuller’s Earth. One wonders whether they used it in the Roman Baths and what effect the mineral water had on it. Its claim to fortune besides being in the Greek play by Aristophanes in 405BC is that it finds mention in a Bible several times including MARK 9.3. “And his garments became glistering, exceeding white; so as no fuller on earth can whiten them.”

In 1888 the Rev. H. H. Winwood M.A., F.G.S., prepared a paper on the Geology of the Bath area, in which he refers to the Inferior Oolite, the Great Oolite and a bed of clay deposit about 150 feet in thickness which separates the two. He wrote that important works had “lately” opened near Midford and Combe Hay. He also wrote about the Solid Rock above Miliping over these “Greasy, unctuous beds”, which calls attention to the past and present land uses in the Bath area.

On February. 8th, 1979 some of our members will recall the talk Mr. D. Anthony of Fuller Industries Ltd., addressed the Club on “Winning and Working of Fullers Earth”. He also furnished us with a trip to the “pit” 2 near Newbury in the dormant volcano field and left with us some literature which he explained the workings preparing this paper.

The Bath deposit was laid down during the Middle Jurassic Period - 160 million years ago. Fullers Earth deposits elsewhere in the U.K. are not so old, having been formed in the Cretaceous Period - about 110 million years ago. The Bath working is therefore somewhat the surface. Mr. D. Anthony told us that the 19 - 27 yards below more calcium than that of their other quality Bath deposits contained quality was not so good as it required more at Redhill and that the Wonder whether the calcium had leached out of the pressing. It makes one however the mine seems to have been retained as a Bath stone above. Future as there is a great deal as yet unworked. Perhaps for the the future the Combe Hay mine will open up and start producing again.

It is a clay mineral formed either by the decomposition of primary rocks in water or from volcanic ash. There decomposition of primary but if the latter the volcano from which the is no doubt about which, pin-pointing the magic of the mineral lies in ash came has not been is much higher than others weight for weight. Its surface area which “activated” by tightly square metres of overall surf to go on the to over three hundred with a mineral acid this can be increased

Electron micro-photographs show that the crystalline layers of the form of thin plates with alumina sheet sandalline particles have silica layers which can also accommodate several laid between two molecules. This causes the one-dimensional reversable water the lattice, which is typical of montmorillonite. Hence its unusual property.

Laporte Industries Ltd. say that no definite chemical composition can be given to Fullers Earth to describe its variability. As to its uses, the importance in the middle ages of the wool trade was followed by methods of absorption and bleaching. During the First World War the Germans found means of using it to make indelible fats consumable. Nowadays it is used in oil refinery, as a bonding agent for well-drilling muds, as a carrier for herbicides and in the construction industry. There are many other uses such as the pharmaceutical preparations.

In a copse near the top of Lansdown there is a small spring where I, as a child, played with the water. I remember how soapy the mud was to the touch. It is now, nearly twenty years later, that I know it to be Fullers Earth and the thought goes through my mind that when the Romans were approaching Bath from the south from what is now the Dunkerton area they must, in digging the Foss on both sides of the Fosseway, have dug through the Fullers Earth with the same effect.

In the early nineteen-thirties the Midford part of the Industry was still in being. Many times I walked through Horsecombe Vale and saw the Engine and Pump House and the pipeline down to the Processing Sheds at Tucking Mill which were sited near the house where William Smith had lived. There was a trolley-way from Midford Road down into the valley and about this time two loaded trolleys left overnight were despatched by vandals down the precipitous slope with dire results.

In a paragraph above it is stated that the composition is variable, but Laporte Industries do produce a formula which is set out below:

(Al, Fe, Mg)4, Si8, O20 (HO)4

“in which the relative amounts of Al, Fe and Mg, are not fixed, represents the main structure of montmorillonite; to this must be added the exchangeable ions, usually Ca, Mg, Na, H and the water content”.

The geological map for the area indicates landslip and areas of foundered strata with two kinds of hatching. It is most noticeable that this lies mostly in the vicinity of Bath. There can be little doubt that there is a relationship between this and the fact that there is a considerable capping of Great Oolite around the hills of this city.

In conclusion I think we should be thinking not that it has proved such a nuisance over the years but that it has been found to be so beneficial in so many different ways. We should also pay a tribute to all those who have been able to exploit this extraordinary mineral to the advantage of Mankind.

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