i believe the merapi logic not believe the voodoo something like that. >> reporter: merapi has killed more than 300 during this eruption and is currently the most menacing of 129 active volcanoes across the indonesian archipelago. another java volcano mount bromo is also in the midst of a big eruption. the islands of indonesia formed at the boundary between tectonic plates of the earth's crust, part of the ring of fire, as it is known. it goes all the way around the pacific and is home to three quarters of the worlds volcanoes and 90% of the earthquakes. here in indonesia, the indo australian plate is crashing into the eurasian plate. as one plate moves beneath the other into the earth's mantle, it changes the pressure and adds ocean water making the mantle melt. this is what feeds volcanoes and earthquakes and no place more so than indonesia. >> so, really, its a test bed of the horrors the volcanoes can be. sumatra and java is it. >> reporter: geologist and author simon winchester wrote the book "krakatoa-- the day the world exploded." the eruption of the krakotoa volcano in java in

miles o'brien filed a blog post on what it was like to travel to indonesia's mount merapi for his recent science story on volacanos. plus it's "tools tuesday" on paul solman's making sense page. every week, paul and his team highlight useful financial resources online. tonight, use an interactive graphic to find out what extending the tax cuts means for you. all that and more is on our web site, newshour.pbs.org. >> ifill: and that's the newshour for tonight. on wednesday, we'll look at the house debate and vote on repealing the military's "don't ask, don't tell" policy. i'm gwen ifill. >> lehrer: and i'm jim lehrer. we'll see you online, and again here tomorrow evening. thank you, and good night. major funding for the pbs newshour has been provided by: >> opportunity can start anywhere and go everywhere. to help revitalize a neighborhood in massachusetts; restore a historic landmark in harlem; fund a local business in chicago; expand green energy initiatives in seattle. because when you're giving, lending, and investing in more communities across the country, more opportunities happen.

and mount merapi in central java is now demonstrating some seismic activity. should we be concerned -- >> about krakatoasome. >> exactly. >> no. >> okay. >> i mean, krakatoa is like a safety belt. it goes off almost every day. the volcanos that you need to worry about are those that don't go off like mount st. helens because when it does go off, it goes off big time. no, krakatoa is a nasty volcano, but it's releasing, it's doing what pharoahe is se people should do more often. [laughter] release its energy. o don't worry. >> if i can ask a question about dictionaries. is it true that you've stopped consulting your dictionaries at home, and you now only look up words on your ipad? >> well, i know where this question comes from. it's the decision -- i was in australia when a chap at oup made this remark that he could not envisage the third edition of the oed being publish inside a hard pay -- published in a hard paper format. and i got telephoned because of the books i'd written about the subject, and i said, quite honestly, i think that's the natural -- i hate