Three) or drying woollen socks or such uses, but care must be used. Never heat damp or glassy rocks such as flint as these contain moisture and air pockets which when heated cause the rocks to pop open. At most, this usually only scatters some embers, but there is always the danger that the rocks will explode more violently. If you can avoid it, it is better not to build a fire place of rocks at all as they become blackened and look unsightly when you leave them behind. The criss-cross fire: Some winters ago, while working for Operation Raleigh, I was involved in the selection of some youngsters for a TV adventure expedition. For part of the selection process they were taken to a remote outdoors location and given various cunning initiative tests to complete, and were filmed in the process. On the second day we awoke to find a heavy blanket of snow on the. ground, so by lunch time everyone was pretty cold and the producer asked me if I could provide a campfire for everyone to eat their lunch around. In all there were I suppose about thirty people which posed a problem. How could I provide sufficient heat to warm so many people from a comparatively small supply of wood?
The solution was to build more than one fire and with a colleague I elected to build three fires in a triangle large enough to accommodate thirty people in the centre. Several small fires are always warmer than one big fire. We chose the criss-cross fire for the job because it burns fast and hot to give a good even bed of embers, and because it is stable unlike the tipi fire. Each fire was about 6ocm square and 90cm tall. They were lit five minutes before lunch was served, and by the time the first of the crew arrived, it was already too hot to stand comfortably in the middle of the triangle! We were all astonished at just how effective the fires had proven, testifying the fact that several small fires are warmer than one larger fire. Despite the fact that the criss-cross is probably the finest fire lay for producing cooking embers, I also use it when I need a very warm fire very fast even in bad weather. It has several times won me bets in such conditions and I think this is because it remains tightly packed as it burns down and it settles on top of itself; the tipi fire for example usually needs the addition of fuel and attention once it has collapsed. Reflector fires: By building a reflector on one side of your fire you will greatly increase your warmth. It can also be used for cooking when baking bread or biscuits (see Cooking). To make a really effective reflector partly enclose the fire with a reflecting wall and then place another reflector behind you to give all round heat; you will be surprised at just what a difference this makes. Reflectors can be made of wood or you could simply place a rucksack or an emergency foil blanket (if carried) by the fire. Fuel So far we have looked at how to light a fire and what shape of fire to build, but these techniques are all dependent upon your burning the correct fuel. I doubt there is any other aspect of backwoods knowhow that will save you as much effort as knowing which woods burn best. Amongst other things, which woods a backwoodsman gathers reveals how skilled he is. In unfamiliar terrain the expert will either make enquiries of the locals or carry out quick experiments bygathering different local woods in each load. As a general rule, woods which are physically soft tend to burn fast and give few
The criss-cross fire is best used for cooking and burns quickly and evenly. 54