背诵篇章 neighborhoods around them or are preparing to do so. The reasons for this confluence of activity are complex but one factor is a consideration everywhere-space. With collections expanding, with the needs and functions of museums changing empty space has become a very precious commodity Probably nowhere in the country is this more true than at the philadelphia Museum of Art which has needed additional space for decades and which received its last significant facelift ten years ago. Because of the space crunch, the art Museum has become increasingly cautious in considering acquisitions and donations of art, in some cases passing up opportunities to strengthen its collections. Deaccessing-or selling off- works of art has taken on new importance because of the museums space problems. And increasingly, curators have been forced to juggle gallery pace, rotating one masterpiece into public view while another is sent to storage Despite the dear need for additional gallery and storage space, however,the museum has no plan, no plan to break out of its envelope in the next fifteen years according to Philadelphia Museum of Art's president 13 Skyscrapers and Environment In the late 1960s, many people in North America turned their attention to environmental problems, and new steel-and-glass skyscrapers were widely criticized. Ecologists pointed out that a duster of tall buildings in a city often overburdens public transportation and parking lot capacities Skyscrapers are also lavish consumers, and wasters, of electric power. In one recent year, the addition of 17 million square feet of skyscraper office space in New York aty raised the peak daily demand for electricity by 120, 000 kilowatts-enough to supply the entire aty of Albany, New York, for a day. Glass-walled skyscrapers can be especally wasteful. The heat loss(or gain ) through a wall of half-inch plate glass is more than ten times that through a typical masonry wall filled with insulation board. To lessen the strain on heating and air-conditioning equipment, builders of skyscrapers have begun to use double-glazed panels of glass, and reflective glasses coated with silver or gold mirror films that reduce glare as well as heat gain However, mirror-walled skyscrapers raise the temperature of the surrounding air and affect neighboring buildings Skyscrapers put a severe strain on a city s sanitation facilities too. If fully occupied the two World Trade Center towers in New York City would alone generate 2. 25 million gallons of raw sewage each year-as much as a city the size of Stanford, Connecticut which has population of more than 109, 000背 诵 篇 章 8 neighborhoods around them or are preparing to do so. The reasons for this confluence of activity are complex, but one factor is a consideration everywhere - space. With collections expanding, with the needs and functions of museums changing, empty space has become a very precious commodity. Probably nowhere in the country is this more true than at the Philadelphia Museum of Art, which has needed additional space for decades and which received its last significant facelift ten years ago. Because of the space crunch, the Art Museum has become increasingly cautious in considering acquisitions and donations of art, in some cases passing up opportunities to strengthen its collections. Deaccessing - or selling off - works of art has taken on new importance because of the museum's space problems. And increasingly, curators have been forced to juggle gallery space, rotating one masterpiece into public view while another is sent to storage. Despite the clear need for additional gallery and storage space, however," the museum has no plan, no plan to break out of its envelope in the next fifteen years," according to Philadelphia Museum of Art's president. 13 Skyscrapers and Environment In the late 1960's, many people in North America turned their attention to environmental problems, and new steel-and-glass skyscrapers were widely criticized. Ecologists pointed out that a cluster of tall buildings in a city often overburdens public transportation and parking lot capacities. Skyscrapers are also lavish consumers, and wasters, of electric power. In one recent year, the addition of 17 million square feet of skyscraper office space in New York City raised the peak daily demand for electricity by 120, 000 kilowatts-enough to supply the entire city of Albany, New York, for a day. Glass-walled skyscrapers can be especially wasteful. The heat loss (or gain)through a wall of half-inch plate glass is more than ten times that through a typical masonry wall filled with insulation board. To lessen the strain on heating and air-conditioning equipment, builders of skyscrapers have begun to use double-glazed panels of glass, and reflective glasses coated with silver or gold mirror films that reduce glare as well as heat gain. However, mirror-walled skyscrapers raise the temperature of the surrounding air and affect neighboring buildings. Skyscrapers put a severe strain on a city's sanitation facilities, too. If fully occupied, the two World Trade Center towers in New York City would alone generate 2.25 million gallons of raw sewage each year-as much as a city the size of Stanford, Connecticut , which has a population of more than 109, 000