51.   But if the signal is not perfect, the size of the screen and the way images are generated exaggerates any defects.

52.   But in the view of some Fed officials, the signals are still too ambiguous to conclude that the economy is actually beginning to slow.

53.   But Pfeiffer thinks the real breakthrough for the marriage of TV and the computer will be when all television broadcast signals are digital, the language of a computer.

54.   But that subtle signal is enough to show up from space, particularly when other clues about coal deposits are combined with the heat data, Prakash said.

55.   But the signals could simply be statistical flukes, and more data could confirm the signal or wipe it out.

56.   But the very clear signal is that the administration is not going to shovel money through the door of the Pentagon.

57.   But the signal is not likely to be heard beyond the House floor.

58.   But there are strong signals that this approach will not work either, from the partisanship that infects most things here to the natural unwillingess to take political risks.

59.   But there was a signal.

60.   But there are strong signals it may come to that.