“Carved instruments can be either completely made of ice, such as horns and percussion, or hybrids, like harps, in which the main body is ice with metal strings attached. … By studying and intricately blending materials — such as homemade clear ice and carbonated water, plus crushed mountain snow — [a master crafter] can make instruments like violins and tune them as close to perfect as nature allows.” And once the performance begins? “Ice is always in motion; expanding, contracting and sublimating away into the atmosphere. Warm bodies melt instruments. Audiences increase temperatures because they are breathing. Instruments need to be re-tuned differently. Some drop several notes, others rise.” – National Geographic