Science writer Baril debuts with a stimulating introduction to ice patch archaeology, the study of human artifacts preserved in ancient blocks of ice. She describes how the discipline began with the 1991 discovery in the Alps of a near-perfectly preserved 4,000-year-old male who appears to have been murdered with an arrow. She also discusses how the unusually large number of hunting artifacts found in Norway's Juvfonne ice patch dating from the Late Antique Little Ice Age (536--660 CE) indicates that massive volcanic eruptions from that period likely destroyed harvests and drove hungry farmers to hunt game in the mountains. Baril offers detailed accounts of the techniques archaeologists use to reconstruct the lives of ancient humans (analysis of pollen grains found in the Alpine corpse's intestines suggest he had eaten three meals and "moved up and down the mountain during his last forty­-eight hours"), and she drives home how the field's existence serves as a bleak reminder of climate change's severity. For instance, she notes that a 10,300-year-old spear uncovered near Yellowstone National Park had remained frozen through millennia of warming and cooling until recent rises in temperature melted the ice enough to reveal the artifact in 2007. This will fascinate and trouble readers in equal measure. (Sept.)