Book Review by Steve Matthews of Bookends.
Wordsworth wrote of "A silent tarn below! / far in the bosom of Helvellyn."
Forget the big lakes, all seventeen which fill the larger valleys. Think of the small lakes, the tarns and the pools, those winking blue eyes in the sunlight, caught in the distance, seen nestling between the hills, splashes of cold grey lapping water in the heart of the mountains.
Dr Alan Smith has counted them all, examined every square on the Ordnance Survey map for any trace of blue. There are 1462 natural lakes and tarns and another 364 water features believed to be wholly artificial (e.g. Reservoirs, Ornamental Ponds, Quarry Ponds, Subsidence and mining features etc.)".
216 of these are sufficiently distinguished to be named on the map and of these 171 are designated tarns. Not surprisingly 152 are to be found in the wettest place in England, in Borrowdale, and a further 220 in the neighbouring area around Scafell.
These lakes owe "their origin to the work of ice which eroded and sculpted the landscape".
"Seathwaite Tarn is a very long narrow lake contained in a rock basin excavated into the volcanic rocks." Little Langdale Tarn was once three times its present size. The valley floor was dug out by three tongues of ice scooping out the valley as they descended with irresistible slow force down from Blea Tarn, Wrynose and Greenburn and then over the millennia a second slow flow of alluvium has been filling the valley floor, creating the shrunken reed-shored tarn we see today.
Higher in the hills are the armchair-shaped hollows, the cirques with steep rocky backwall and enclosing sidewalls, with the water escaping, seeping over the edge and splashing down to the valley below. The ice rotated in these pudding-basins, cutting and cutting so that many of these tarns are exceptionally deep and often, like Blea Tarn, almost perfectly circular. The beautiful, silent Bowscale Tarn "lies in the thermally metamorphosed Skiddaw Granite". Bleaberry Tarn is on the Ennerdale Granite but its backwall is cut into volcanic rocks.
Alan Smith reports on each tarn, its shape, the rock on which it is founded and the ice movements which produced it.
The vast majority of these patches of water in the landscape were created by areal scouring of the bedrock by mobile ice sheets. This knock and lochan landscape was formed as the weight of mobile ice sought out the weak points, the cracks and fissures in the underlying rock. It is not just the larger tarns, - Angle, Burnmoor, Blelham, - and waters - Devoke and Skeggles - but all the myriad pools which pattern this special landscape.
Other tarns, like Broadcrag Tarn and Lambfoot Dub, are found on rock ledges. Some lie in basins between sharp, rocky aretes: others on saddles below summits.
Yet others, like Overwater, have been naturally dammed as debris brought down by other streams has formed a fan-shaped dam.
Dr Alan Smith is a passionate geologist, the sort of man you want at your side as you walk the fells explaining the shape of everything as though it were moulded by giant, ice-cold hands.
This is a compact book, hugely informative, packed like the others in The Landscapes of Cumbria with a wealth of detail, neat maps and diagrams, and fine photographs. An excellent series produced by an expert with a passion for geology and a deep love of the Lakes.
Unfortunately, as time passes, these lakes will fill with debris, become marshy beds and then these pearls among the hills will merge into the grassy fells.