As a child, riding with friends on our bikes, we at one time came up against a rather nasty donga (gulley) in the veld. We could jump over it, but not get our bikes over easily. Then someone had a bright idea and a few days later we rode down with a piece of wood rather precariously tied to her bike. We dropped it across the donga and were horrified to watch it settle, one side up and the other too far down the other side to be of any use as a bridge.
So we returned with a borrowed measure (from my father’s garage – the metal type that you could extend to see a distance) and measured the gap. We then went around a few of the family garages and workshops until we found a piece of the required length, ‘plus a bit’ so that we could be sure it would work. Our idea of “plus a bit” later proved to be the key to success.
Again, tying it to a bike, we rode out again. We laid it across the donga, and immediately we had access to the far side, on our bikes and free to roam even farther. (You may be glad to know I returned the measure to the same place in my father’s work area, and he never knew I had borrowed it.)
We had little idea of stabilising our rickety little bridge, and were maybe lucky that it didn’t twist sideways as we rode over, dumping us and our bikes in the donga.
None of us became civil engineers, so it just goes to show that one early success is not a determinant for a later career.
Recently at a conference, I heard a lovely statement. Engineers don’t just build bridges to “stay up” they build them “not to fall down”. A few people looked baffled, but I understood him to say that it’s no good a bridge just for sitting there unused on a balmy summer day, it must last through the range of climatic and other conditions you want to specify as possibilities.
A bridge designed for an area where the wind never exceeds a gentle breeze, and designed for foot passengers only, may not be expected to remain there in a hurricane, or if someone drives a car over it. However a bridge designed and built for those factors would endure them, and other similar conditions and loads.
An engineer once tried to describe to me a construction that altered its shape and therefore became more ‘rigid’ with weight on it, yet with no load, could be flexible to move slightly with severe wind conditions. It sounded very cool, but the maths was beyond my tiny brain.
The bridges between friends are similar. If we have a friendship for happy conditions only it is unlikely to survive any stresses. A friendship that is really strong survives absence, too much time together, sad and angry times, and under pressure is stronger or more flexible, as needed, like that interesting bridge design.