Local cave art?

A few local caves contain interesting features that may or may not be early art works. Three examples from a number of different local caves are presented below simply to whet the appetite of those interested in the subject and to suggest that the presence of cave art in North Wales cannot simply be ruled out......

Example 1. Identification and photo by John Blore

Example 2. Identification and photo by John Blore

Example 3. Identification by John Blore

Four comparisons are shown below of accepted cave art from French and Spanish caves that share some similarities......

Comparison 1. Les Combarelles, Dordogne

Comparison 2. Grotte d'Aldène, Carcassone

Comparison 3. Le Mas Dazil, Ariege

Comparison 4. La Clotilde, Cantabria

There is however, a stumbling block in seeking confirmation that a site actually does contain early cave art: There are very few acknowledged experts in the field and those that exist can be reluctant to confirm examples found by others, particularly if the others are regarded as amateurs. In the case of a suspected discovery of cave art, the advice would therefore be to take detailed colour and B & W photographs (illuminated from various angles) and take careful measurements. Examine the site carefully for any flowstone deposits overlying the art work, no matter how thin, as this can be dated fairly accurately, thereby providing a not-later-than date for the art. Finally, publish full details of the find and your reasons for suspecting it to be an early work of art. Flintshire Historical Society publish annual Memoirs, or 'Archaeology in Wales' is the publication of the Council for British Archaeology Wales . Both organisations will consider papers from non-members. If published, at least it means your work cannot be ignored.

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Interested in searching? - A few non-expert tips....

1. Before setting off

Potential cave art is likely to be difficult to identify on a caves rock surface: It may be worn by the passage of animals, it may lie beneath layers of modern graffitti, or it may simply have been eroded by weathering. The keen amateur therefore needs to be able to know what to look for. The simplest way is to familiarise yourself with as many photographs of cave art as possible. Then at least, certain shapes are more likely to stand out. Here are a few suggested sources to get you started.....

Links:

Cave art, Wikipedia: https://en.wikipedia.org/wiki/Cave_painting

Cresswell Crags: http://www.stone-circles.org.uk/stone/creswellcrags.htm

Cresswell Crags: http://www.antiquity.ac.uk/projgall/bahn300/

Cresswell Crags: https://www.dur.ac.uk/archaeology/research/projects/all/?mode=project&id=639

Lascauz Cave: http://www.bradshawfoundation.com/lascaux/

Niaux Cave: http://www.bradshawfoundation.com/niaux/

Blombos Cave: http://www.visual-arts-cork.com/prehistoric/blombos-cave-art.htm

Armintxe cave: http://www.bbc.co.uk/news/world-europe-37654544

Books:

Cave Art by Paul Bahn (2012): http://www.bookdepository.com/Cave-Art-Paul-G-Bahn/9780711232570?ref=pd_detail_1_sims_b_p2p_1

Cave Art by Jean Clottes (2010): https://www.amazon.co.uk/Cave-Art-Jean-Clottes/dp/0714857238

The Caves of France and Northern Spain by Ann & Gale Seiveking (1962). Plenty of used copies available for around £5 or £6.

Four Hundred Centuries of Cave Art by the famous Abbe Breuil (1952). A classic large format tome, but not cheap...... if you can find a copy. Used copies appear from time to time from about £50 or £60 upwards. Its 416 pages are packed with illustrations and photos of engravings and paintings.

Lascaux by the almost-as-famous Fernand Windels (1950). Another classic large format publication of 140 pages.

2. Method tips

Choose a cave : To examine a cave thoroughly takes time and patience, so select a short cave with sufficient space to take photos, and with comfortable working conditions. Known archaeological caves perhaps provide the most potential, although few caves can be ruled out entirely. The few important archaeological caves are likely to be gated and locked. If choosing such a cave to examine for art, don't be put off: The first point of contact is Cadw. If they grant access, they may send someone to accompany you on your visit, but they should not rule out any genuine applicants.

Engraved art simply requires a good light source directed obliquely (from several different angles) in order for variations in the rock to cast the best shadows, hence making visual identification easier. It's not really practicable to make a thorough photographic record of a cave for engravings, as the images will vary enormously depending upon the direction and angle of the light source. A camera will of course help if any suspect areas are identified. If the sun shines into a cave at sunrise or sunset, this may also enhance your searching.This was it seems, how the Creswell Crags art was first identified. It takes longer than you might imagine to examine a cave by any method: Each square metre of surface needs to be illuminated from many angles, and patient visual examination can take ages. For this reason, only be accompanied by someone who is as keen as you and intends assisting in the search!

Pigment-based art may be so faded or eroded that visual identification with the naked eye is difficult or impossible. There is however, a method that makes badly faded colours more pronounced and therefore easier to identify. It is of course, computer software. You first need to install a host programme, then install the cave art programme as an add-on......

The host programme is "Image J" and can be downloaded at: https://imagej.nih.gov/ij/

The cave art add-on is developed by John Harman and called "D Stretch" at: http://www.dstretch.com/.

Both are free to download, although you may need to contact the developer of D Stretch to explain why you want to use the programme before he'll send it over as a zip file.

In order to use this computer method you'll need to take a set of fairly high-quality digital photos. If checking an entire cave, the images need to be taken systematically along the entire length of the cave and should include the walls and ceiling. Photos can be complimented by markers indicating the distance from the entrance and whether the image is of the left wall or right wall (i.e. "4R" = the right-hand wall 4 metres from the entrance). Taking the photos can best be achieved using a camera mounted on a 180 degree swivel-headed tripod positioned in the centre of a passage. If you have to take more than three images to capture both walls and ceiling at one camera location, you may find a wider angle lense helpful. Once a complete photo-record is made, the results can be examined in detail at home using the software. But it does take a long time..... and before too long you start imagining cave paintings on the screen in front of you!
(With special thanks to cave archaeologist Dr George Nash for his kindness in suggesting this programme).

The software offers many different profile options, each enhancing a specific colour. Four examples of the various profiles are shown below, using an image of Dulas Cave (Abergele). No cave art as been identified at this cave, but the examples simply demonstrate the potential of the software. The first image is unprocessed. This is then followed by four 'D Stretch' processed photos of the same image............

3. Cave art-hunting equipment (additional to normal caving gear)

A. LED site-type flood light

B. LED hand torch

C. Camera

D. Tripod with a 180 degree swivel head

E. Tape measure, pen and paper

F. Computer and software for pigment identification (not needed in searching for engraved art)

These are explained below.....

A. An LED site-type flood light (warm white: between 2400 to 3000 kelvins): Great as an all-purpose site light, but its chief advantage is when searching for pigments: The warmish light brings out the colours far better than the cooler whites, and helps D-stretch in processing the images later. The minimum output to look out for when purchasing is about 30w. You can manage with a 20w light, but you may need to increase exposure times in roomy passages, which in turn increases image noise.

B. An LED hand torch (warm white to cool white: 3000 to 4000 kelvins): Ideal when searching for engravings. The cooler light offers a more contrasting 'black and white look' which helps in examining shadows. A hand torch is preferable to a site-type lamp as you'll need to shine the light from many different angles in order to examine a particular area thoroughly. For this reason, your camera will need the ability to be triggered remotely, from wherever you are aiming the torch. A typical torch is the excellent Xtar flashlight: https://www.amazon.co.uk/Platoon-Lumens-Tactical-Flashlight-Simple/dp/B00WNVXYXO/ref=sr_1_1?ie=UTF8&qid=1482166958&sr=8-1&keywords=%22xtar+flashlight%22
Even with a bright torch such as this, you may still need to take longish exposures, but this does allow you to 'paint' the wall or ceiling with light to give an even spread of illumination, and thus creates evenly distributed shadows.

C. A camera capable of producing reasonably high quality images: These days, even inexpensive compacts can fit the bill. But in order for D-stretch to be most effective it needs as much digital information as possible. If using a camera with inter-changeable lenses, to keep things simple, choose a lense that provides a field of view sufficient to include both walls and ceiling in just three images. Also allow for a small overlapping area which helps when aligning images later (if you need to join two together to examine the mid-area in more detail).

D. A Tripod with a 180 degree swivel head (or home-made bracket) makes the whole operation quicker and helps avoid missing areas or duplicating the areas being photographed. As a rough guide, if a single passage is say 4m wide by 2m high and 20m long, starting 2m in from the entrance, you should be able to position the tripod at 3m or 4m intervals along the cave for each set of three photos (4m of wall being the field of view of the camera with each image overlapping a little). Hence the completed set should total about 15 photographs (taken from five tripod locations).

E. Tape measure, pen and paper: The tape measure can be used to measure the distance from the entrance of each tripod location for each set of three images (left wall, ceiling & right wall). Mark a piece of paper for example '1L' (1m from entrance, left wall) and place this on the floor just within the cameras field of view. (no need to mark ceiling photos as they will be between left wall and right wall images). You can of course, not bother with markers if confident that you will take your series of photos in reliable order as you advance along the cave, moving the camera at a uniform distance each time. But in practice, you may find that for many reasons, you take several shots of the same area, and it can become rather too easy to mistake the order of photos and invalidate your record, particularly if you actually discover something and need to pin-point its position within the cave.

F. Computer and software for pigment identification (not needed in searching for engraved art).