O what depressing, dreary, dismal times we live in. Our island is under siege by the threat of foot-and-mouth disease, the freezing elements are wreaking havoc everywhere, and to cap it all, those of us who venture into church today will be told, in the vernacular or otherwise, not to cheer up but to memento homo, quia pulvis es, et in pulverem reverteris. Bad as things are, they will be worse: our destiny is dust.
Edward Fitzgerald, of Khayyam's Rubaiyyat fame, had a slightly more optimistic attitude, a rather Keynesian approach to this impending descent along the path to dusty death:
Ah, make the most of what we yet may spend,
Before we too into the Dust descend;
Dust into Dust, and under Dust, to lie,
Sans Wine, sans Song, sans Singer, and - sans End!
Meteorologists, on the other hand, insofar as they memento the pulvis at all on this or any other day, worry about it only insofar as it may affect the weather. Indeed they have a special name for dust, or at least for the dust that permeates their atmosphere: they call it the konisphere, the "shell of dust".
The atmosphere contains a host of micro-sticks and microstones, thousands of foreign bodies that make even the cleanest airmass anything but pure.
On a clear day there are some 300 solid particles in every cubic centimetre of air, while in more murky conditions the number grows to many tens of thousands. It is only the extreme modesty of their dimensions that makes them barely noticeable; most of the time they are too dilute really to bother us.
These dusty motes are of many sizes, shapes and substances. Every wind that sweeps across a desert scoops up many tons of pulverised rock to scatter far and wide. The soils of the world are littered with tiny fragments of vegetable fibre, lifted by the gentlest breeze to be wafted here and there.
A thousand different plants and trees contribute pollen to the atmosphere, and from our kitchens and our factories come soot and smoke and other tiny particles.
As if this were not enough, every now and then the Earth itself explodes in a great volcano, to spew tons of powdered rock into the air. Even the ocean, as every drop of spray evaporates, adds a pinch of salt into the air we breathe.
And the konisphere collects a daily dose of ashes up above, the remains of thousands of incinerated meteors or shooting stars, and also, sadly, these days down below from, ditto, pigs and cows.
Have a nice day!