When the weather turns into a blast furnace, water can be a cool friend. Nothing like a refreshing dip to dampen the heat.But water also can be a deadly substance, especially if you plunge into the wrong body of water.City kids for years have been spitting in the eye of danger by plunging into the nasty waters of the Schuylkill River. Truant in judgment, they sometimes get torpedoed by tragedy.It happened again Sunday. Some city boys opted to swim in the river, they said, because the city raised the daily fee from $1 to $3 at the Schlegel Park pool and they couldn’t afford it.The sun-splashed Sunday suddenly was splashed by panic when two brothers waded into danger. The older boy, 13-year-old Ronald Michel, died trying to save his younger brother, who fortunately was saved by others.The real tragedy is that the drowning wouldn’t have happened if the boys had the money to swim in a pool. Economics is hardly a gelatinous structure. Either you have the currency or you don’t. These boys didn’t and now one of them is dead.When you’re young and hot, your instincts often are at war with your judgment. You think you’re invincible, never vulnerable.And if you have meager financial resources, you pay no heed to the danger of swimming in unsupervised and unsafe waters.It’s shaping up like a long, hot summer. Hopefully our city youth will save their pennies and use the Schlegel Park pool or find their way to Blue Marsh.One river drowning this summer is one too many.