342 COLUMBIAN HISTORICAL EXPOSITION AT MADRID. 



It is probable that by certain adventitious or accidental circum 

 stances the American potters may have produced a vernis or glaze on 

 an occasional object; however, glazes were perhaps not desired, as the 

 porous character of the ware was its chief good quality, giving cool 

 ness to water, etc. With kilns, better fuel, giving stronger firing, 

 there is no reason why the American potters should not have been 

 able to fuse the slip forming an enamel, or on stoneware clay to have 

 secured the vernis which precedes the glaze. 



The color of pottery is usually due to the form in which iron exists 

 in the clay and the thoroughness of firing. Iron in clay is nearly 

 always in the form of a carbonate, which burns to a red oxide. When 

 there is a silicate of iron the clay burns to cream color. Strong firing 

 burns out carbonaceous materials. 



In the course of this investigation the broad field of the origin of 

 form and ornament could scarcely be touched. 



It appears that the first stages of an art like pottery are marked with 

 uniformity; then as specialization takes place centers of styles appear, 

 until the higher advances are made in a region where environment and 

 germane causes work together w^ith man s adaptability for the attain 

 ment of the results. 



Generally, in these collections two classes of pottery can be distin 

 guished, (1) Cult pottery and (2) domestic pottery. 



THE POTTERY OF MEXICO. 



Iii the great collection of Mexican antiquities exhibited in Madrid 

 there was a vast quantity of pottery, as well as stone and metal. 

 These objects, under the care of Dr. Troncoso, of the Mexican National 

 Museum, were grouped ethnically, and included many tribes of the 

 Mexican stocks. 



As a general impression, the pottery seems to belong to one great 

 culture area, with slight differences among the Mayas, Aztecs, etc. 

 The two classes of pottery Avith regard to function can be distinguished 

 here, namely, pottery for domestic and other uses and cult pottery, 

 images, &quot; idols,&quot; masks, vases, etc. 



The art of the modern potter of Mexico may tell us something of 

 the ancient processes. 



The manufacture of modern pottery in Mexico is usually in the hands 

 of men, and there is also now division of labor. The wheel and kiln 

 are used, but pottery in a great variety is now made as in former times; 

 there is, indeed, an unbroken continuity of the potter s art in Mexico 

 without deterioration on the whole. The ancient art can thus be recon 

 structed by the present art. 



A detailed description of the processes of the Indian potter of Gua 

 dalajara and the collections made by Dr. Edward Palmer will cast 

 much light on this subject. 



