REYKJAVIK (Reuters) – A volcano that erupted in southwest Iceland for the second time in less than a month appeared to be significantly less active on Monday despite indications of magma still flowing underground. “A black day” read the front page headline of Icelandic daily Morgunbladid across an image of bright-orange lava fountains and houses burning in the town of Grindavik, some 40 kilometres (25 miles) southwest of the capital Reykjavik. Although volcanic activity has eased since Sunday, the eruption centres is a high-risk area and new fissures could open without warning, the Icelandic M…