Oh dear. It is August and soon Washington's heat will bake our brains. We will fall prey to the silly season, when Venutians and Martians are spotted floating overhead and at least one inventor announces a plan for an automobile that is powered by dust.

Dog days the Roman called the heat-struck time, caniculares dies , blaming their discomfort on the rising Dog-Star, whose passage they believed intensified the heat of the sun.

Noel Coward gave us another canine caution when he wrote that only "Mad dogs and Englishmen go out in the midday sun."

With such advice dogging our days, let us abondon the formal dinner party and give into silliness.

It is no feat to build castles in the air, but how many of your friends over the age of 10 have had the recent pleasure of building a sand castle? Put a tarp in your driveway, tack together a sandbox 4-feet long by 4-feet wide by 8-inches deep and fill it with sand. Hechinger's carries 50-lb. bags at $2.19 each, and it would take about 10 bags to fill your jerry-built box.

With the help of the garden hose and several sets of sand toys, you can sponsor a castle contest, with a couple assigned to each corner of the sandbox. Since sand is going to get into everything anyway, serve beer and sandwiches and, of course, sand tarts. Winners get a beach ball. Or maybe sand.

The age that brought us sand castles also taught us the cooling virtues of water fights. Plastic water pistols are cheap, buckets of watery ammunition can be stashed anywhere and everyone can be warned to come in bathing suits or clothes that need washing anyway.

Like all wars, water fights are bound to escalate, with someone inventing the water-filled balloon bomb or introducing the cannon of water fights: the garden hose. Naturally, the team that captures the hose wins and since everyone is a mess anyway, it's a good time to serve up buckets and buckets of spicy crabs.

If you like your silliness in less messy form, give a posy party where everyone must communicate in the language of flowers. Serve mint (virtue) tea and tomato and basil (good wishes) saidwiches and have lots of different flowers in jugs around the room to facilitate conversation.

Hand someone a head of lettuce and you've informed them they suffer from coldheartedness. Tuck a sprig of parsley behind your ear to announce you're feeling festive. Give someone a rose wrapped round in ivy and you've committed yourself to love accompanied by marriage and fidelity. Offer a hibiscus to one whose delicate beauty you want to praise. Stick a bachelor's button in your lapel to indicate you've opted for celibacy.

Carrying an endive around, supermarket prices to the contrary, signifies your frugality. Twine a vine in your hair and you've announced your intention to get intoxicated and would do well to steer clear of any guests wearing a saffron crocus (Beware of excess).

Do not come to a post party wearing dead leaves. The assembled floral linguists will know at a glance that you are feeling very, very sad and will not want to talk to you.