The Hawaiian Volcano Observatory (HVO) record books are annual journals in which field observations of eruptive activity at Kīlauea and Mauna Loa volcanoes, on the Island of Hawaiʻi, were compiled by HVO staff for most years from 1912 through early 1966. In addition to descriptive observations, the record books also contain hundreds of annotated photographs and sketches, as well as temperature and transit measurements. When photographs are included, the camera settings and film types used are noted. The field notes, sketches, and photographs used to compile the record books provide an unparalleled record of eruptive activity and were the basis for published newspaper reports and periodic bulletins, such as the Hawaiian Volcano Observatory bulletins and The volcano letter.  

HVO staff also painstakingly prepared a second copy of each early record book, virtually identical to the original, complete with photographs and sketches. The original version of the record book was kept at HVO, while the duplicate went to the Hawaiian Volcano Research Association, which was created by a group of Honolulu, Hawaiʻi, businessmen to promote HVO’s work. The Hawaiian Volcano Research Association, which dissolved decades ago, held the duplicate books in Honolulu, where they were more readily accessible to the public. After 1923, HVO stopped duplicating the books—at least, no duplicate records for subsequent years have been found. During the decade of the 1940s, preparation of the record books stopped altogether. In 1952, compilation of the record books resumed and continued, with long gaps, until early 1966. Entries in these later volumes are sparse, and these books are little more than photo albums of the episodic eruptions of Kīlauea. 

The original record books were held at HVO and, later, at Hawai‘i Volcanoes National Park. In 1972, the original record books for the years 1912 through 1939 were transferred to the Bishop Museum, in Honolulu, for safekeeping. These record books are now stored in archival boxes at that institution (accession number 172.265). The duplicate set of record books held by the Hawaiian Volcano Research Association were bound into volumes at an unknown date and turned over to the U.S. Geological Survey. This set of record books, spanning 1912 through 1923, is now housed in the rare book room of the U.S. Geological Survey Library in Reston, Virginia (catalog number 220(950) H3d). The record books for 1952 through early 1966 remain in storage at HVO. After 1955, typed annotations were no longer placed in the record books, and only photographs, most with captions, were included. Although the volumes titled “Record Book” end with the 1955 volume, the photograph albums that followed are similar, and the record book designation is retained for simplicity. Note that the photographs in these albums were not all originally arranged in chronological order.