GEOI.OGY AND TOIMX ;HA1MI V OK HAWAII. 155 



visit. All MCcouiit ot the ascent iiiadi' at thai tiiuc was rcconlcd in Ari-lnhald 

 Menzie's journal, in 17!)4, and remained uninihlished until brought to light 

 through the researches of Prof. Hitchcock and pi-inted for the first time in 

 Thrum's Annual for 1008. ^[r. Menzie cah-idated the height n\' tlie mountain 

 by use of tlu^ l)ar(uiieter without corrections for the \ afiations in temperature ^- 

 and made it but forty-one feet less than tlu^ [)resent accepted altitude, l-'roni the 

 time of Menzie's ascent to th(^ ])resent the mountain has been undei- abnost con- 

 •stant observation, and man\' parties of competent observers have attained the 

 summit. Its extensive and interesting history has been full\- recorded and com- 

 piled in two elaborate monographs, one by Prof. Hitchcock and the other l)y 

 Dr. Brigham. both appearing in 1909. To these works the reader is referred 

 for detailed accounts of the long series of eruptions, the bare enumei*ation of 

 which are almost beyond the scope of this chapter. 



History of the Eruptions of Mauna Loa. 



However, it is of interest to know that eruptions were reported on .Manna 

 Loa in 1780 and again in 1803; the first fully recorded eruption occurred in 

 1832, and in June of that year ^launa Loa is reported, by the Rev. Joseph 

 Goodrich, to have ejected lava from several places in the side of the mountain, 

 presunial)ly some little distance below th(^ summit. From that time until the 

 last eruptive tlow^-^ the lava has always issued from the weak places in the side 

 of the mountain, tliongh the caldera at the summit has on numerous occasions 

 become active, forming a lake of lava without iiows taking place. 



Of the fifteen eruptions resulting iii flows that have occurred on Hawaii 

 within the last one hundred years, twelve have had ^lanna Loa as their source. 

 The eruption of 1843 was presaged by activity in the crater of ^lokuaweoweo 

 1)ut after a few hours the fire died down in the crater and reappeared on January 

 10, 1843, in two places on the northeastern shonlder of the mountain, at about 

 11,000 feet elevation; from these, lava ran in a l)road sheet down the side of 

 the monntain for about sixteen miles direetlx" towards the peak of .Mainia Kea, 

 fiowing continuously for a period of four weeks. In the saddle between the two 

 monntains the stream widened out and spread over the plain, being four and a 

 half miles across in the widest part. One branch extended a considerable 

 distance down tov;ards Waimea on the west, evidently uniting with a former 

 erui^tion known as the Keamuku flow. 



The flow of 1851, beginning on August Sth. A\as announced by a remarkably 

 brilhaiit display accompanied by detonations in the suinmit crater. This tlow is 

 said to have occnrred from an opening on the west side of the monntain about 

 1,000 feet lielow the summit and. to have extended for ten miles westerly in the 

 direction of Kealakekua. It lasted only about four days, and is not commonly 

 shown on maps. 



In the following year, on February 17. 1S.")2. light was aii'ain seen on the 

 summit, and within a short time lava broke out on the iiorthei-n slope of the 



'- Wniicli would i-pfhicp the altitude, as giveu by liim. liy alxiut seventy feet. '•' In 11)07. 



