‘The aspect of this large and stately white column, as it heaves in sight from the dim reflection of the torches, is grand and impressive. Visitors have seldom pushed their inquiries further than two hundred or three hundred yards beyond this pillar. This column is about fifteen feet in diameter, from twenty to thirty feet in height, and regularly reeded from the top to the bottom. In the vicinity of this spot are some inferior pillars of the same appearance and texture. ‘I have thus given you an imperfect sketch of the mechanical structure and appearance of the cave. It only remains to mention its productions. ‘The first in importance is sulphate of magnesia, or Epsom salts, which, as has been before remarked, abounds throughout this cave in almost its whole extent, and which, I believe, has no parallel in the history of that article. This neutral salt is found in a great variety of forms, and in many different stages of formation, sometimes in lumps, varying from one to ten pounds in weight. The earth exhibits a shining appearance, from the numerous particles interspersed through the huge piles of dirt collected in different parts of the cave. The foregoing remark applies with truth, not only to the surface, but to three feet below it. This is the greatest distance hitherto examined. The walls are covered in different places with the same article, and reproduction goes on rapidly. With a view to ascertain this fact, I removed from a particular place every vestige of the salt, and in four or five weeks the place was covered with small needle-shaped crystals, exhibiting the appearance of frost. ‘The quality of the salt in this cave is inferior to none, and, when it takes its proper stand in regular and domestic practice, must be of national utility. With respect to the resources of this cave, I will venture to say that every competent judge must pronounce them inexhaustible. The worst earth that has been tried will yield four pounds of salt to the bushel, and the best from twenty to twenty-five pounds. ‘The next production is the nitrate of lime, or saltpetre earth. There are vast quantities of this earth, and equal in strength to any that I have ever seen; and when potassium can be more conveniently obtained than at present, the manufacture of saltpetre must be a lucrative pursuit. There are also large quantities of the nitrate of allumina or nitrate of argyl, which will yield as much nitrate of potassium or saltpetre, in proportion to the quantities of earth, as the nitrate of lime.