From HISTORY OF CLAYTON COUNTY, IOWA Vol. I, Robert O. Law 1916
Sand Mosaics - Another industry peculiar to McGregor was the making of beautiful and artistic pictures in bottles from the many colored sands found in the Pictured Rocks near McGregor. This industry was so unique that it attracted attention not only in this country but in Europe, and the following is an extract from an article published in "Lectures Modernes", of Paris in July, 1903:
"About twenty years ago, an American deaf mute, Andrew Clemens really sought to use in decoration (picturing) the multicolored sand which is found in abundance in the vicinity of McGregor, Iowa, and succeeded, before his lamented early death, in developing the idea to a high degree of perfection. His brilliant conception, however, seemed in danger of being forgotten, when Mr. W.S. O'Brien, manager of the Union Telegraph office at McGregor, took up the problem in such hours of leisure as his professional avocations left him, and brought it happily to a successful solution. Let us visit, then, the studio of the Sand Artist. The equipment of the "mosiaste" is simplicity itself. His "palette" comprises a case of boxes in fan form, divided into compartments, each containing sand of a different shade, forty-one in all, and none of them artificial. A pencil of wood is his only "brush". With a small spoon he transfers from the several compartments the sands into a glass bottle, the size and form of which he selects according to the object or combinations he wishes to represent, then by means of the little wooden tools, Mr. O'Brien arranges the sands just as a painter applies his colors on a canvas. He succeeds in this way of accomplishing many beautiful effects. The sand, once in position in the bottle, is pressed strongly but with precaution so as not to shatter the glass envelope; then the mouth of the bottle is cemented. This done, no shaking or shock can disarrange the varicolored particles encased in this hermetically sealed enclosure.
"One would imagine that the sand must be pasted or glued upon the interior surface of the glass that it could hold so firmly in position. Nevertheless we affirm after personal verification that the sand has not undergone any manipulation whatever. It is used simply dry and as nature gives it, just as anyone can pick it up from the veins in the "Pictured Rocks" near McGregor. Nothing more magnificent to contemplate than these layers and veins of sand combining all the colors of the rainbow, diversified, clearcut, distinct, separate. Upon these monster mountain mosaics of nature the sun's rays play with marvelous effects, while in the midst of the hills are running and singing little brooks and rivulets, jumping like frisking lambkins over rocks and forming sparkling cataracts in their way down to their homes in the bosom of the great "Father of Waters" a the foot of the bluffs.