288 
Dr. Herschel’s Observations to investigate 
Dispersed Ridges or Nodules make Corrugations. 
Nov. 17, 1800. The surface of the sun appears richly filled 
with very small broken or dispersed ridges, which produce the 
corrugated appearance. 
Feb. 18, 1801. The high parts of the corrugations contain 
numberless separations, like small nodules, which leave room 
for the indentations to be seen between them. 
Corrugations change their Shape and Situation ; they increase , 
diminish, divide , and vanish quickly. 
Dec. 27, 1800. i h o'. There is a pretty large corrugation 
near a small opening, which serves me as a direction to find the 
place. Its indentation is about four diameters of the opening 
from it; and 10 or 16 degrees north-preceding. 
i h 5'. I have seen the corrugation again ; and find its inden- 
tation larger than it was, and farther from the opening. 
i h 10'. It is vanished ; and several other such very minute 
changes have taken place. 
i h 12'. Within a diameter of the opening, and a little north- 
following it, is an oval indentation, nearly as large as the 
small opening. 
i h 15'. Its shape is altered; and it is divided into a corru- 
gation, with two indentations. 
i h 35'. Both are entirely gone. 
Jan. 18, 1801. Between two clusters of openings, that are 
near each other, there are some incipient openings, which 
resemble coarse corrugations, and establish a step between 
small openings and pores of indentations. I shewed them to 
my friend Dr. Wilson, who happened to be upon a visit to me, 
