I CROSSED PATHS with a turtle Thursday. He appeared to be headed for the Jones Falls - the waterway, not the expressway. I was bound for a nearby Sears store to get fetch air conditioner parts. We were both engaged in seasonal rituals.

As legions of turtles before him have done, he'd gone on springtime maneuvers. Emerging from a stand of trees on the east side of the 41st Street overpass, he meandered west, eventually destined, I presumed, for the fragrant, muddy environs of the Jones Falls.

There is a distinct "creeky" aroma to the waterway. Songwriter John Prine has described a similar stretch of water in his native Kentucky as a place where "the air smelled like snakes." To this turtle, the Jones Falls must have smelled like his summer residence.

It was not summer yet, not officially until June 21. But it felt like it, especially late this week when the air was heavy with humidity, as thick as cream of crab soup.

Just as it is written in the turtle's genetic code that he must meander, so it is written in mine that on the stickiest, most uncomfortable days of the year, I must heave air conditioners into windows. We were both drawn to the flood plain of the Jones Falls below I-83, where Sears, one of the nation's largest retailers, sells one of the world's most elusive parts. That would be part No. 5300126809. Known as both a "curtain" and an "accordion," it's a collapsible rubber panel that fills the gap between the air conditioner and the window frame to keep out bugs and air.

Traditionally, it is the part that cracks shortly after you have girded your loins and tossed the heavy air conditioner into a window. In prior years, I have replaced damaged rubber panels with pieces of cardboard, a cheap but tacky substitute, prone to sagging in wet weather. This year, I armed myself with spare panels at Sears, loading up with more "accordions" (at $9 each) than you'd find on the Lawrence Welk Show.

My reliance on air conditioning marks me, of course, as a non-native species. While we "come-heres" depend on humming machinery to remove humidity from Maryland's heavy air, there are some locals who weather the summer without it. They speak of "artful shading," of talc in the morning and of gin in evenings as ways to tolerate, even enjoy, the stultification of July and August. I endorse all these measures but find they fall short of the comfort produced by a whirring condenser.

Not all native Marylanders are averse to air conditioning. The two living in my house, for instance, are in favor of it, as long as I am the one who puts the air conditioners in their bedroom windows. I had delayed this task until Thursday, waiting to see if our two sons would spring into action themselves. I had even placed one of the window units in prominent view within their lair, the third floor of our house. Instead of taking the hint, though, they seemed content to migrate to lower floors of the house, where the non-natives reside, enjoying the comfort of a central air-conditioning system.

So Thursday evening, as thunderheads boiled in the western sky, I was sticking my head out of a top-floor window, installing an air conditioner. As often happens in a standoff between parent and child, my patience had run out. The kids seemed to think that since air conditioning was so important to me and since I "wanted the job done right," I would eventually install the window units. They knew their quarry well.

I began by pulling AC accessories from winter storage: the 2-by-4s that fit under one air conditioner holding it steady, and short pieces of plastic pipe that wedge between the top of the sash and the frame, preventing the window from being thrown open and the unit from tumbling out the window.

Then the fury and majesty that is a Maryland thunderstorm hit, altering plans and tossing timber. In my neighborhood, the storm picked up the 2-by-4s I had set on a windowsill and playfully flicked them onto the back porch roof. Later, over on the Eastern Shore, a storm struck a more telling blow, toppling the Wye Oak, a 100-foot-tall beauty that had stood its ground since the 1500s. It was an impressive reminder from Mother Nature about who sets the agenda on June evenings.

Chastened, I resumed my attempt at getting the air conditioner in the correct posture, so it drips water outside, not inside, the window. This is an annual struggle between the shape of the air conditioner, the lip of window sash, and my brain. This year, I lost the opening round. For the first two hours of operation, there was no interior drip. But four hours later, there was a puddle on the wrong side of the window.

It turned out not to be an urgent matter. After the storms moved through, the temperature and humidity dropped. The air turned cool and sparkling. On such days, locals who disdain the need for air conditioning are in their glory. I, however, dread the return of humidity. So I am readying a comfortable domestic shell that, like my friend on 41st, I can withdraw into when I feel threatened.