On the road between Pateley Bridge and Grassington just outside Greenhow lies a curious structure with the remnants of a stack chimney base, a kiln and a long stone lined flue. This is actually the remains of Toft Gate Lime Kiln which played an interesting role in Nidderdale’s industrial heritage.
I stopped recently on the way back from a visit to Scar House Reservoir to explore the site further and investigate more about the origins of the structure.
One important thing to note is the kiln is situated in the middle of limestone country. Limestone has been the basic ingredient of lime mortar since Roman times, but since the medieval period lime has also been used as an agricultural fertiliser. More recently it has been used as a flux in the steel making industry.
The process for getting lime from limestone involves “burning and slaking”. The limestone needs to be burnt at high temperature (also known as calcining), to release Carbon dioxide and produce quick lime. This can then be stabilised by mixing with water (a process called slaking), then dried to produce a powder called lime.
The lime was often spread on fields to help the soils become more alkali and increase their fertility. Alternatively the powder could be mixed again with water to produce a lime mortar for building.
What we see at Toft Gate dates back to the 19th century and a thriving lime production industry in the area. There are lime kilns throughout the Dales and I passed another smaller kiln recently whilst walking between Grassington and Kettlewell. Toft Gate Lime Kiln has a rare design and with being so well preserved clearly shows how it would have worked at the height of its usage.
Whilst there are no records of its ownership, it is known that the Ingleby Family of Ripley Castle held limestone rights in the area from the 17th century, so it is assumed it maybe has something to do with them. Whilst not anywhere near as well preserved, there are remnants of two other lime kilns on the hillside reasonably close by.
Around the kiln you can see holes in the ground nearby where the limestone was quarried for burning. The limestone would have been blasted out of the quarry walls and then broken by hand using picks and hammers to create fist sized pieces to add into the kiln.
It is believed that the kiln dates to 1860 and you can see the long flue, the kiln itself and the base of the chimney as you walk around a short trail. The type of furnace has been identified by industrial archaeologists as a “continuous burn, dual feed, vertical kiln furnace”. The flue and the chimney improving efficiency and taking away the fumes.
The kiln was a tall, square stone built structure with a central circular shaft. Crushed limestone was fed into the top of the shaft and the fuel, most likely coal, was passed into the shaft lower down into 8 fireboxes to create a burn zone or firing level in the mid-section of the shaft. The temperature in the kiln would have exceeded 800 degrees.
The kiln was built using sandstone and limestone blocks and you can still see some of the iron ties holding it together. There is also evidence of fixings for a steam crane on top which would have allowed the limestone and fuel to have been dropped into the kiln.
The impressive flue is actually 70m long and built of limestone blocks, snaking down the slope.
Interestingly there was also evidence of a small reservoir built close by to store water and supply the site.
The resultant burnt lime and coal ash was then extracted from the bottom of the kiln. There would have been waiting carts to transport the lime across the dale to fulfil previously placed orders.
It would have been a hot, noisy, environment to work in. Work would have been hard, conditions brutal and often children were employed to help break up the limestone. This is a far cry from the peaceful location today with its stunning views back over Nidderdale with its sheep and rolling fields.
If you stop for a visit, it is next to Coldstone Cut – a massive artwork next to a Hanson quarry which is still in operation. I will blog about Coldstone Cut separately but both are well worth a visit.