2 LIMEKILNS NEAR BATHURST

 2. LIMEKILNS NEAR BATHURST

I have selected Limekilns for the first blog entry, as this appears to be the first place in NSW where a limestone cave was reported and explored (1821). Previously,  explorer George Evans had observed and recorded the presence of limestone in several places near Canowindra (1816). The discovery of limestone was significant because of its use in making mortar and for agricultural purposes. Previously, sea shells had been gathered in large quantities around Sydney and Newcastle, including from aboriginal middens, and roasted to make quicklime which was then "slaked" by adding water to produce slaked lime, usually referred to as lime.

Limestone is essentially calcium carbonate and it is commonly derived from marine shellfish. Fossils of these are frequently found in limestone and associated sedimentary rocks.

A little chemistry:  calcium carbonate (calcite) CaCO3; 

calcium oxide (quicklime) CaO; calcium hydroxide (slaked lime or simply lime) Ca(OH)2 

Limekilns is a district about 25 km north-east of Bathurst in the central west of

NSW. Following the exploratory trip of George Evans in 1813/14 and the proclamation of Bathurst as the headquarters of government by Governor Macquarie in 1815, settlers soon began moving their sheep and cattle beyond the Blue Mountains. Prominent among them was William Lawson, a member of the first party to cross the Blue Mountains in 1813. The following paragraph is compiled from the journal he kept and forwarded to Macquarie.

"William Lawson, one of the first Europeans to cross the Blue Mountains west of Sydney in 1813, continued to explore to the west and in November 1821, while touring the country around Bathurst, found himself in the hamlet of Limekilns, then called Limestone Hills. He was shown a cave and recorded in his journal (Lawson 1821) on 8 November:  "Camped at the Limestone Hills, here government has a kiln built for burning of lime for the use of the settlement which proves to be the very best quality. Here is a curious cave through a solid rock of limestone. Its entrance is very narrow. At nine o’clock at night I took four men with three candles and proceeded into it about one hundred yards. At the end is a fine pool of clear water. In many places for several yards together I was obliged to creep on my hands and knees. The inside of the cave is very curious and well worth seeing. I got some fine specimens. Came out at one o’clock in the morning."

The Limekilns Caves. (Evening News, Sydney NSW. Saturday 18th May 1889.)

"Mr. Samuel Taylor, brush manufacturer, of Queen's-place, Sydney, who has an estate at Limekilns, between Bathurst and Sofala, about seventeen miles from the former place, has just returned to town. He has been engaged for some time past in opening one of the numerous caves on his property. This has been done to a depth of some 300 ft, and the cave was found beautifully hung with stalactites. If visitors will patronise the caves, Mr. Taylor states that he will be pleased to carry on the work of opening them up still further." 

This article may have led to the following one, a few months later. The cave subsequently became known as "Benglen Cave" and retains that name today. An article appeared in the "Bathurst Free Press and Mining Journal"" of Wednesday 29 January 1890, which suggests that the cave was well known at Limekilns but little known in Bathurst. Here is a quote from the article.

"Just recently, however,a proper entrance has been made by blasting the rock which covered the hole leading down into the first chamber — for it was simply a hole in the side of the hill, and an easy descent has been cleared and a safe archway built up, so that now the first chamber can be entered without any difficulty — provided, of course, that Mr. Tobin is there with his key for the door that has been erected across the squared opening. This first chamber is a space of about 20 ft by 20 ft., with a height varying from 8 ft. to 8 in., the roof being, if it were level, like the inside of a huge boiler lid. And here the first glimpse of the stalactites are obtained, and the fact made plain that we are in a cavern made by water operating upon limestone.Yet we also learn at a glance that there is much more than limestone present. On the sides and in the roof are strata of conglomerate, made up of fossil shells, bones, and even pieces of petrified wood, all pressed together and undergoing a secondary process of disintegration or further solidification, the face of the conglomerate in places being coated with a glistening covering of limerock. "

It appears that a great deal of vandalism had taken place since Lawson's visit and continued until the cave was reduced to the muddy tunnel it is today. (Having never visited Benglen Cave, I can only repeat what reports in the various speleological societies journals say.)

LIMESTONE CAVE AT LIMEKILNS.

"Geological Branch, 16 Sept. 1898.

Sir,— In compliance with your instructions I have the honor to report on the application of W. F. Hurey, Esq., M.P. for the opening up and improving of a Limestone cave near the Limekilns Post Office. The cave is on private property, portion ?, parish of Jesse, county of Roxburgh, 17 miles N.N.E. of Bathurst. Its entrance has been improved by excavation and by the erection of a gate. The cave runs northerly for about 100 feet. It is from 8 to 15 ft. wide and from 2 to 10 feet high. At 80 feet from the entrance there is a "basin" formation. At 120 feet some small drapery formations and stalactites may be seen. There are occasional groups of broken stalactites. The formations are all dull coloured and of little beauty, and in many cases have been mutilated.

The cave is dirty and uninteresting, throughout. An objectionable feature is present in the shape of foul air which was met with at 225 feet. I do not think that there is any-thing to justify the Government in resuming the land for the purpose of improving the cave. I have indicated on a sketch herewith, the position of the cave, and also, of the limestone outcrops in some of which are the quarries in the beautiful variegated marble known as the "Fernbrook marble." I have, &c., O. TRICKETT, Licenced Surveyor." 

This introduces us to Oliver Trickett. He knew caves better than anyone else in those days. Part of his job was the supervision of caves in NSW and his maps and photographs are the best there are. Here is the "sketch" he referred to taken from the 1898 annual report of the NSW Department of Mines.

The name given to the limestone is the Jesse Limestone, and it is part of the Limekilns Group of Lower to Middle Devonian age. It, and the associated shales and sandstones, contain marine fossils of that age. It outcrops in two distinct belts, the left being  generally known as the Limekilns limestone and the right (more crystalline) as the Fernbrook Marble.A syncline strikes approximately NE-SW with the two belts outcropping on either side.

The map is taken from the 1986 revision of "The Limestone Deposits of New South Wales"by Lishmund, Dawood and Langley.