•Ill Transactions. — < 'hemistry. 



from grit and lit for the potter without elutriation. In the Wade District, 

 extending to Riverhead, we have a very varied assortment of clays, fit for 

 all purposes of pottery material with the exception of the finer wares. From 

 Mercury Bay I have received samples of fine, white, unctuous clays, hut as 

 to the extent of the deposits I have no information. In the Waikato, near 

 Hamilton, there are some excellent clays, the biscuit of which is of a pure 

 white. Some of these clays have been worked up into medallions, slabs, 

 and ornaments by Mr. Wright, who has resided a long period in that por- 

 tion of the district engaged on pottery work, and whose workmanship is in 

 the highest degree ornate. Though these clays are so excellent they have 

 not been proved as to extent, and I think it questionable whether they will 

 be found free from iron in more than small deposits. And here we have 

 the drawback at present of lengthy rail carriage to the centre of population 

 in the district. At the coal mines, Kawakawa, Whangarei, Taupiri, and 

 Miranda, we have the refractory clays accompanying the coal measures, but 

 these will be of value only in the rougher articles of pottery, owing to the 

 presence of iron pyrites in nodules or finely distributed, and shrinkage, from 

 the amount of bituminous material present. I come now to the last of the 

 locations where I have found any great extent of clays for varied purposes, 

 and so situated as to be within reasonable distance of fuel and adjacent to 

 this city where the articles may be brought to market and for export. I 

 allude to the Drury and Papakura basin, overlying which are the plastic 

 clays. Here, over several square miles of country, we have clays from the 

 whitest material, giving a biscuit of great purity to yellow, grey and blue 

 clays yielding biscuits from a light cream to a deep rich red, which will give 

 a terra cotta of great beauty. I have analyzed some of these deposits, and 

 here append the results : — 



Yellow Red Clay Blue Clay (pinkish 



(terra cotta). creamy biscuit). 



Silica 59-2 62 



Alumina 29-9 29"5 



Oxide of Iron 9"7 6-3 



Lime trace trace 



Magnesia trace -6 



Water 1-2 1-6 



100-0 100-0 



In reference to these deposits, I do not for a moment claim any dis- 

 covery with respect to them, as Dr. Hochstetter, in a lecture delivered at 

 the Mechanics' Institute in 1859, calls attention to these beds, advising the 

 establishment of potteries for the manufacture of earthenware, and further 

 states " remarkably suitable clays of every necessary variety have been 

 shown to exist in the neighbourhood," and also furnishes the results of two 



