The Rosenwach Tank Company, of 40-25 Crescent Street, Long Island City, which is celebrating its eighty-second anniversary, is one of a very few rooftop-tank coopers left in the city. (Its workmen, though, now belong to the carpenters' union.) No one has ever come up with a better way of making a rooftop water tank than by girdling a cylinder of wooden rooftop water tank than by girdling a cylinder of wooden staves with metal hoops and adding a conical roof, and New York, which has thousands of cylindrical wooden rooftop water tanks with conical roofs, couldn't exist without them. The tanks are here because the water that comes into town through the aqueducts will rise to about the sixth floor without any assistance but has to be pumped to tanks on top of taller buildings to provide water pressure on their upper floors. This scheme provides plenty pressure, because the water arrives at those floors by falling straight down. Rosenwach has built and installed well over half of the city's tanks. Many of New York's Rosenwach tanks were constructed in twenties, under the regime of Julius Rosenwach, the father of Wallace Rosenwach who is the current president. Julius Rosenwach moved the business to Greenpoint from Grand street, Manhattan, fifty-four years ago, as soon as the B.-M.T. Canarsie line was finished. The Rosenwach shop is still in Greenpoint, and its offices moved from Greenpoint to Long Island City only last year. Harris Rosenwach, Julius's dad, came to the States in 1894 from outside Warsaw, where he'd made bathtubs and tubs for storage and cooking. "Wood was the major material for fluid vessels in those days," Wallace Rosenwach says. Harris Rosenwach got a job with a copper company on Pike Street, later Grand Street, and when the man died, two years afterward, he bought the shop for fifty-five dollars-money he'd been saving up to bring his family over. Soon plenty of New York tanks were sporting the distinctive Rosenwach emblem, a four-sided "R" at apex of the conical roof, and there was quite enough money to bring everyone over. "You can't draw a New York skyline without water tanks," Wallace Rosenwach says. He's fifty-six, a jolly Teddy bear of a man. "You look down from the top of a high building and see a sea of tanks. We're stupid enough to insist on manufacturing our own tanks. They last forever, unfortunately." Rosenwach water tanks are made of grooved staves that fit snugly together and are enclosed by galvanized iron hoops. The staves are cut in Rosenwach's Greenpoint shop - a clean, well-lighted place- on a machine that Wallace Rosenwach invented. It simultaneously cuts both ends of a stave flush, grooves the edges, and drills a small hole halfway along either side- "at the push of a button," he says. The rank roofs are made in the shop, too, in prefabricated sections. Installing a tank on top of a building- a typical four- "R" tank is thirteen feet in diameter and twelve feet high, and holds ten thousand gallons of water- Rosenwach's field manager, George Vassiliades, and his crew of between a dozen and twenty workmen, all of whom have to wear hard hates and steel-toed shoes on the job, start by erecting a steel platform as a base for the tank; then they put up the staves, which are at first held loosely together by wooden dowels connecting the small holes on adjacent staves; then they bind the tank with ropes until the metal hoops can be put on, with the dowels still in place; and, finally, they put on the roof. They can dismantle an old ten-thousand-gallon tank in the morning and have a new on in its place that night. If you want to know how many feet high a tank you're looking at is- this is a rule of thumb-count the number of hoops and add one. The staves are made either of California redwood or of white cedar (juniper) from the South or of yellow cedar from the West Coast. The conical roofs are plywood; they were originally made of yellow pine and later of cedar, but those woods don't last more than eight years. "Plywood lasts forever, unfortunately," Wallace Rosenwach says. These days, only about a third of the Rosenwach business is building rooftop water tanks. Another third of the business is maintenance, and cleaning, and repairs, and the rest is building-of redwood or Southern cypress-industrial tanks for firms like du Pont, Gumman, Pfizer, and I.T.T. (Acids can't corrode cypress.) Rosenwach also has two subsidiaries in Long Island City- one making planters, and the other making cooling towers for office building air-conditioning coils. "All the fats in the Lever Brothers soap you use are digested in our tanks," Wallace Rosenwach says. "All the colors in the very good grade of lipsticks are made in our cypress tanks. So are New York State wines. Pickles, food-no matter what you do in life each day, a wooden tank either enters in or affects you. We made a forty-foot redwood tank twenty feet high with eighteen-inch portholes for I.T.T. to put porpoises in, for sonar experiments. They wanted wood, not steel, because wood wouldn't bounce the sound around confusingly. Oceanography, one of the newest sciences, is being aided by one of the oldest sciences. Every giant panda in the United States has a Rosenwach tank- all two of them! My daughter went down to Washington and saw Ling-Ling and Hsing-Hsing playing with and old tub, so we made each of them a little redwood bathtub. They had a marvelous time-they threw the tubs around, couldn't break 'em. There's a Rosenwach tank that's a house- a hunting lodge n Windsor, New York, on top of a hill. Thirty-four feet in diameter, eighteen feet high. Pre-engineered in Greenpoint. Took three men four days to put it up. No nails! Never can be cornered in that house." Rosenwach started getting into redwood planters in a big way two or three years ago- the Rockefeller Center "Atlas" is now supported by a Rosenwach planter- and recently it has also been turning out hot tubs and decking form rooftop gardens, not to mention a safety attachment for the ladders on the Brooklyn Union Gas tanks in Maspeth which prevents any-one climbing the ladders from slipping more than six inches. Wallace Rosenwach was trained as an engineer before the Second World War, but he didn't want to have anything to do with the family business, and took a job at Douglas Aircraft. Then, over in the Pacific with the Seabees just after the war, when he had time on his hands before being demobilized, he made a cigar humidor for his father, out of thirteen different kinds of wood, that looked just like a miniature Rosenwach water tank, complete with the four "R"s. "On the side I put a sign that said 'Rosenwach & Son,'" he says. "It was my way of telling him 'Maybe'. It's funny how you get into things in this business. Armstrong tiles-you know what Armstrong's original business was? One hundred years ago? Home-canning corks. They had all this cork left over, so they started making wall coverings and then floor coverings. Their first linoleum had lots of cork in it. Whatever we make, we want to stay in New York. We cater just to New York- we're so much a part of New York. We see our efforts all over the city."