The excerpt represents the core issue or deciding factor on which you must meditate, and is drawn from The Time Machine by H. G. Wells: running transversely to the first. This appeared to be devoted
to minerals, and the sight of a block of sulphur set my mind
running on gunpowder. But I could find no saltpeter; indeed, no
nitrates of any kind. Doubtless they had deliquesced ages ago.
Yet the sulphur hung in my mind, and set up a train of thinking.
As for the rest of the contents of that gallery, though on the
whole they were the best preserved of all I saw, I had little
interest. I am no specialist in mineralogy, and I went on down a
very ruinous aisle running parallel to the first hall I had
entered. Apparently this section had been devoted to natural
history, but everything had long since passed out of recognition.
 The Time Machine |