MILLER— SPROUL OBSERVATORY ECLIPSE EXPEDITION. 275 



occurred at Goldendale ; p-p is therefore the amount the arch has 

 changed. If p-p' is positive for a given point, that point is farther 

 from the center of the sun, when the sun was ecHpsed at Brandon 

 than when it was ecHpsed at Goldendale twenty-five minutes before. 



After the first set of measures was made, the zero line was rede- 

 termined and all angles and distances remeasured, so that each set of 

 measures was independent of the others except the same size of each 

 vectorial angle was retained. The different series of measures were 

 made on different days, the last series being made about six weeks 

 after the first were made, so that I believe little, if any, prejudice 

 originating in the earlier measures was carried into the last set. 



Measures of the Arch Around the Southeastern Prominence. — 

 This prominence is a few degrees east of the South Pole. There 

 are five well defined arches on the equator side of this prominence, 

 the inner one of which is measured. The table shows the results. 



I. An Arch Around the Southeastern Prominence. 



The quantities p and p in the " first measures " of this arch are 

 from center of the sun to the inner boundary of the arch ; the other 

 measures from this arch and all the others are to the middle of the 

 stream forming the arch. The first measure in each series is always 

 for a point near the limb of the sun, and is in consequence very 

 indefinite. 



2. An Arch Around the Pyramid Prominence. 



Toward the Pole side of this prominence there are four well- 

 defined arches ; one of these was measured. The arches on the 

 Brandon plates seem to curve more than those on the Goldendale 

 plates. The results are shown of four sets of measures on three 

 different days. 



