"Am I nervous?" asked Heru Suparwaka, watching the needle of the seismograph sketch a crazy route across the page, accompanied by a high-pitched whine. "Of course I'm nervous."
Mr Heru is part of a small team monitoring Mount Merapi, one of the world's most active volcanoes, from an observation post high on its slopes. The area, on Indonesia's Java island, has been on red alert for weeks, since Merapi began spewing out lava and clouds of gas and hot ash. But since last weekend's earthquake, its activity has intensified dramatically, sparking fears of an imminent eruption.
The volcano lies 30 miles north of the epicentre of the quake, which claimed 5,427 lives, according to latest figures. With 20,000 people injured, and up to 200,000 homeless, it might seem that this portion of central Java has suffered enough. But now the scenario of one major natural disaster followed by another appears more probable than not.
The inhabitants of the farming villages that dot Merapi's fertile slopes were evacuated to temporary camps on lower ground earlier this month. But many have trickled home, against official advice, and on Sunday, the day after the earthquake, the 425-strong population of one village, Turgo, returned en masse.
The people of Turgo know Merapi's wrath. When it last erupted in 1994, killing 66 people, 37 were from that village, located four miles from the crater. But at least the volcano is a familiar threat. Earthquakes are not, and it was fear that propelled them back to Merapi's shadow. They are more frightened of another big earth tremor than of being engulfed by boiling lava.
"We feel safer here," said Sumardi, a farmer. "If an eruption comes, at least you can run. You can't run from an earthquake."
Normal life has resumed in Turgo, despite the sour smell of burning in the air, and the street signs that warn of looming danger. Children play in the road, and women hang up clean washing. Apart from the relative risks of leaving or staying put, many villagers feel a spiritual attachment to Merapi. The volcano is shrouded in superstition. Once a year they perform a ritual to placate it, offering up gifts of rice, green coconuts, and cow's liver.
"Merapi can be a threat or a friend, depending on how you treat it," said Jayadi, another Turgo farmer. "It gives us prosperity, by making the soil so fertile, and providing us with sand for construction. When it is angry, like now, it is because we are greedy and selfish, and our leaders are corrupt and don't look after the people properly." Mr Jayadi was sitting in a surveillance post at a bend in the road, with a pair of binoculars trained on Merapi. The post, which local people man around the clock, is linked with the monitoring station in the neighbouring village of Kaliurang. If calamity appears about to strike, Mr Heru will let them know, and they will use a megaphone and sirens to tell villagers to flee.
Mr Jayadi confidently expects Merapi, which killed 1,300 people in 1930, to "fill 16 rivers with its lava" this time. But even those injured in 1994, such as Murjo Utomo, who was badly burnt by hot gas clouds, prefer to take their chances. Mr Murjo, whose body is a patchwork of skin grafts, said: "If the lava comes from one direction, I'll run in another." While the villagers remain on constant alert, with bags packed, their sense of impending doom is backed by science. Volcanologists say the earthquake disturbed a fragile dome at Merapi's peak, and warn that if it collapses, it will cause a big eruption of rocks, hot gas and lava.
Mr Heru said that lava was flowing up to 2.5 miles, in various directions. An extra mile or so would bring it to Turgo and Kaliurang. Another village, Deles, is even closer. Hot clouds are being emitted three times more frequently than before the quake, and smoke is rising 3,000 feet into the air. At night the villagers see the red lava trails; by day the clouds of gas billow out.
"The last few days have been scary," said Mr Heru. "Activity has increased significantly, and if it keeps on like this, a major eruption will surely happen."