NO. 4 SITE FOR SOLAR-RADIATION STATION MOORE I7 



summit and in a small canyon to the northeast of the shrine. Unfortu- 

 nately, some Bedouin goat-herders polluted this spring near the close of 

 our second visit, so that during the third visit it was necessary to have 

 our water packed up on camels from the large monastery. In order to 

 insure its coming from the monastery and not from some water-hole 

 as bad or worse than the polluted spring, we arranged that the water 

 boy should carry a paper from me each trip, which would have to be 

 stamped with the monastery seal in the Head Monk's office and 

 returned to me when he brought the water. 



Mount St. Katherine or rather Gebel Zebir, adjacent to it, is the 

 highest mountain in the Sinai Peninsula and in all of Egypt, being 

 about 8,600 feet above sea-level. The mountains of crystalline for- 

 mation, in which this peak is located, are among the most rugged to 

 be found in the world, and make of this desert a wilderness in every 

 sense of the word. The mountain lies at latitude 28° 31' N. and longi- 

 tude 33° 58' E. It is nearly in the center of the triangular mountainous 

 region forming the southern end of the Sinai Peninsula. To the north 

 of this triangle sandy table-lands slope toward the Mediterranean. 



The view from Mount St. Katherine is grand indeed. It towers 

 above the varicolored mountains and chasms to be found on all sides. 

 Particularly do Mount Sinai (Gebel Musa), Gebel El Shomer, and 

 Gebel Serbal stand out in the north, south, and west, respectively. 

 Beyond the Sinai mountains toward the west lies the Gulf of Suez, 

 where, although it is over 30 miles distant, one can count the ships on 

 a clear day. To the south the Red Sea appears, and to the east are 

 seen stretches of the Gulf of Akaba, separating the Sinai Peninsula 

 from Arabia. On most days the mountains of the Egyptian and 

 Arabian mainlands could distinctly be seen. 



On our first visit we occupied the mountain top from March 9 

 until April 18, inclusive. During this period we experienced some 

 most excellent skies, some moderately good, and others very hazy. 

 The clearness of the excellent skies was remarkable, equalling, if not 

 excelling, the very best that northern Chile and Table Mountain, 

 Calif., have afforded. The absolute absence of haze near the sun per- 

 sisted until sunset, a most unusual thing. On two or three such days 

 there was a very thick, sharply defined layer of haze extending per- 

 haps a half degree above the horizon in the west at sunset. When the 

 last vestige of the solar disk buried itself in this sharp layer of haze 

 a distinct green ray was seen ; and strangely enough, we saw another 

 flash of green as the sun disappeared behind the distant Egyptian 

 mainland. On the other hand, during the first visit, there were nearly 

 half of the days with very hazy skies, but with only three days lost by 



