enough to hold in heat as well as air, and stiff enough that the breeze won’t mould it against your body. The books say you should bite a hole in the corner of it to breathe through and then enter it head first. This makes sense: warm air rises and stays in the bag. However, I’ve never been quite desperate enough to bite a hole in something that cost me five shillings.
Two are not twice as warm as one in a bag, unless the bag’s a very big one. If the bag gets tight it compresses your clothing and the bits of you pressing against the outside get very cold indeed. There are, however, group bags: these are specifically designed for several people to get miserable in together.
PLASTIC BAG FOR PLEASURE PURPOSES
Some of us are too mean to buy a proper bivvybag, and some of us just like to see how much we can do without. I come into both categories. So here is the technique for primitive plastic travel.
If plastic bags get wet on the inside, the way to stay dry is to stay outside the bag. A foam mat is one of the things you probably didn’t bring, and the double layer of plastic underneath is insulation of a sort as well as groundsheet.
When it starts to rain, you can postpone the damp by moving under a nearby tree. When the rain starts to drip through the leaves, it’s just possible it may already have finished raining outside.
Otherwise, it’s time to get into the bag. Position it with the feet end slightly uphill. This means that condensation in the bag has a chance to trickle out the entrance. It also means that raindrops on the outside will drip off the doorway rather than trickling back inside. If you hold the entrance well open, air can get in and evaporate some of the condensation.
You wake up moist but warm. It’s the next night, the crawling back into a bag that’s already damp, that’s going to be really horrible. So the advice is not to do that next night, but to head off the hill to civilisation with its youth hostels and shops selling proper breathable bags.
However, it may quite possibly not rain at all. In which case you simply keep going until you run out of muesli. You lie late to let the sun take the dew off the plastic, amble down to the village whose lamps had lightened your night-time, and discover that, late though you lay, it’s still two hours too early for the shops.
POLYBAG FACTS
The basic polythene survival bag should cost between £5 and nothing at all – they may be given away free with outdoor magazines. A fertiliser sack does the same job more cheaply, though the bedtime reading printed on the outside is less entertaining. (The big-bag style is a good size: it’s important to wash out all traces of the previous contents as fertiliser damages the skin.)
The more the bag weighs the more effective it is – but the more it weighs, obviously. Eight to twelve ounces is a good balance between heaviness and uselessness. It should be long enough to be able to get right inside with boots on, and fold down the end so as to let the rain drip – this means 2m/7ft. If planned for two, it should be big enough to hang loose around them rather than stretched tight about their bodies.
The multi-person shelter does offer a significant weight saving, quite apart from the conviviality. The three/four person ‘Windblokka’ weighs 600g/1lb 4oz and is made of proofed ripstop nylon. It costs about £45. It’s designed for sitting up in rather than lying down and going to sleep.
One night under the moon in a plastic bag should persuade you that you want more nights under the moon, but in something other than damp plastic. Rawhide? Potato sacks? Stout Harris tweed? In the next chapter we’ll study various historic bivvybags even less accommodating than polythene.
Chapter 2 BIVVY HISTORY
Brian an augury hath tried
Of that dread kind which must not be
Unless in dire extremity,
The Taghairm called; by which, afar,
Our sires foresaw the events of war.
That bull was slain: his reeking hide
They stretched the cataract beside.
Crouch’d on a shelf beneath the brink,
Close where the thundering torrents sink,
Midst groan of rock, and roar of stream,
The wizard waits prophetic dream…
The period from 1900 to roughly 1969 was a dark age of outdoor technique.
When the Marathon was reintroduced as an Olympic sport a hundred years ago, it was considered unnecessary and unsporting to drink water along the way. As a result, Marathon runners tended to collapse and die at the 20th mile. Certainly, 26 miles and 300 yards were too far for all but the toughest and most athletic: too far for the entire female sex. Today, 30,000 people every year cover the distance, some of them only moderately fit, some of them dressed as chamber pots and crocodiles. And at every mile marker they pass a drinks station. But we can be sure that Pheidippides, who was the original Marathon runner, knew about the importance of water. So did the Aztec post-runners, who covered over a hundred miles a day up and down the Andes.
When the Dyhrenfurth expedition attempted Kanchenjunga in 1930, each expedition boot, once its massive crampon was strapped onto it, weighed in at 2.85kg/6lb (5.7kg/12lb the pair). Professor Dyhrenfurth seems to have considered this a good thing, as it strengthened character along with legs. And yet the Roman soldier, as he padded along the ridge of High Street, knew all about lightweight footwear. Legionaries wore hob-nailed leather sandals; auxiliaries preferred the lightweight boot called caligula. One report describes the caligula as very comfortable, and better than the modern military boot. The upper was cut from a single piece of leather, laced all the way up the front and sometimes left open at the toe and heel. The sole-pattern resembled that on a modern pair of trail shoes – designed to optimise the distribution of the walker’s weight. Today’s boot design may just about be catching up with the Romans. It would be interesting to run a comparative gear test against a pair of Brashers…
Back in the dark days of 1970 I headed up into Glen Affric for a week of Munro-bagging. On my back was the state-of-the-art rucksack: a dangling pear-shape of stout canvas. Any self-respecting Roman soldier would have flung that pack into the bog. It added 10lb to the effective weight. And that effective weight already included the tent of the time: 11lb of cotton, and hemp cordage, with wooden poles connected with ferrules of solid iron. The 33 pegs on their own weighed more than a tent of today.
And yet, 100 years earlier, imaginative Britons had been sleeping out under tents with a total weight, including poles and groundsheet, of nothing at all. In 1878, the writer Robert Louis Stevenson appears to have invented the bivvybag.
‘This child of my invention was nearly 6ft square (i.e. before sewing into a bag)… a sort of long roll or sausage, green waterproof cart cloth without and blue sheep’s fur within.
A tent, above all for a solitary traveller, is troublesome to pitch, and troublesome to strike again; and even on the march it forms a conspicuous feature in your baggage. A sleeping-sack, on the other hand, is always ready – you have only to get into it; it serves a double purpose – a bed by night, a portmanteau by day; and it does not advertise your intention of camping out to every curious passer-by.’
So here is bivvy-literature’s first recorded night out in a bag. Like many after him, RLS leaves it rather late to select his bedroom…
‘The rain had stopped, and the wind, which still kept rising, began to dry my coat and trousers. “Very well,” thought I, “water or no water, I must camp.”
The wind roared unwearyingly among the trees; I could hear the boughs tossing and the leaves churning through half a mile of forest; yet the scene of my encampment was not only as black as the pit, but admirably sheltered…
I tied Modestine [his donkey] more conveniently for herself, and broke up half the black bread for her supper, reserving the other half against the morning. Then