Other experiments on which I worked dealt with location of the Zenith in the sky for quick determination of latitude and longitude from stars and telescopic studies of the moon, an old hobby of my master, Shaler. I have long been convinced that Kilauea lava resembles moon lava in the craters it builds, and my special interest is that Mauna Loa and Kilauea build structures of basalt, small and large, which are earth experiments imitating the moon on a smaller scale. The astronomers say their field is the stars, the geologists must explain the moon. As a matter of fact, one geologist has made a start. My classmate J. E. Spurr, who after retirement to Florida from work as U.S. Geological Survey geologist among the faults and lavas of the far West, published books on the comparison of the moon with geology. In view of increasing attempts to explain moon craters by impact (Baldwin), I feel that experienced volcanologists should also take a hand in moon science. Larger arcs of circles on the globe, the Aleutian Islands for instance, resemble moon features and are deeply volcanic. Furthermore, magnificent detailed photographs of the moon from modern telescopes are available to volcanology. I spent my summers at Hawaii National Park, becoming consulting geophysicist. Dr. Chester K. Wentworth of the Board of Water Supply became geologist. The laboratories were extended to a seismograph station seven miles up the northeast flank of Mauna Loa, but operation of the original cellar adjacent to the Volcano House was continued. A basement under the Natural History building of the Park held seismographs, Finch’s office and library, and Loucks’ shop. In 1948 Observatory work was returned to the administration of the Geological Survey, and a volcanologic branch in Denver took over Dr. Powers to make airplane studies of the Aleutian Islands. This was under Mr. Walter Frederick Hunt, in charge of geology, U.S. Geological Survey.