“If I could only remember the chemicals!” said Sin Saxon.  She was down among the outcrops and fragments at the foot of Minster Rock.  Close in around the stones grew the short, mossy sward.  In a safe hollow between two of them, against a back formed by another that rose higher with a smooth perpendicular, she had chosen her fireplace, and there she had been making the coffee.  Quite intent upon the comfort of her friends she was to-day; something really to do she had:  “in better business,” as Leslie Goldthwaite phrased it to herself once, she found herself, than only to make herself brilliant and enchanting after the manner of the day at Feather-Cap.  And let me assure you, if you have not tried it, that to make the coffee and arrange the feast at a picnic like this is something quite different from being merely an ornamental.  There is the fire to coax with chips and twigs, and a good deal of smoke to swallow, and one’s dress to disregard.  And all the rest are off in scattered groups, not caring in the least to watch the pot boil, but supposing, none the less, that it will.  To be sure, Frank Scherman and Dakie Thayne brought her firewood, and the water from the spring, and waited loyally while she seemed to need them; indeed, Frank Scherman, much as he unquestionably was charmed with her gay moods, stayed longest by her in her quiet ones; but she herself sent them off, at last, to climb with Leslie and the Josselyns again into the Minster, and see thence the wonderful picture that the late sloping light made on the far hills and fields that showed to their sight between framing tree-branches and tall trunk-shafts as they looked from out the dimness of the rock.

She sat there alone, working out a thought; and at last she spoke as I have said:  “If I could only remember the chemicals!”

“My dear!  What do you mean?  The chemicals?  For the coffee?” It was Miss Craydocke who questioned, coming up with Mr. Wharne.

“Not the coffee,—­no,” said Sin Saxon, laughing rather absently, as too intent to be purely amused.  “But the—­assaying.  There,—­I’ve remembered that word, at least!”

Miss Craydocke was more than ever bewildered.  “What is it, my dear?  An experiment?”

“No; an analogy.  Something that’s been in my head these three days.  I can’t make everything quite clear, Mr. Wharne, but I know it’s there.  I went, I must tell you, a little while ago, to see some Colorado specimens—­ores and things—­that some friends of ours had, who are interested in the mines; and they talked about the processes, and somebody explained.  There were gold and silver and iron, and copper and lead and sulphur, that had all been boiled up together some time, and cooled into rock.  And the thing was to sort them out.  First, they crushed the whole mass into powder, and then did something to it—­applied heat, I believe—­to drive away the sulphur.  That fumed off, and left the rest as promiscuous as before.  Then they—­oxidized the lead,