AMERICAN INSTITUTE. 475 



After some general conversation on the nature of wliite lead and its uses 

 in painting, the mode of adulterating it ■with sulphate of barytes, &c., &c., 

 and upon the modes of applying paint to roofing, the Association adjourned, 

 havihg resolved to continue as a subject the " Novelties of the Fair." 



Polytechnic Association of the American Institute, ) 



October l^l.h, 1859. } 

 S. D. Tillman, Esq., Chairman, pro tern. John Johnson, Esq., Secre- 

 tary, pro tern. 



The numbers present being smaller than usual, gave rise to some com- 

 ments from several members upon the apparent neglect of the secretary in 

 not advertising the meeting. Accordingly, on motion of Mr. Seeley, a 

 committee of three, viz. Messrs. Seeley, Garbanati and Garvey, was ap- 

 pointed to confer with the Trustees, in order that the meetings might 

 be regularly advertised for the future, and proper provision be made for 

 having them correctly reported. 



Mr. Garvey, to open the discussion, called attention to Parkhurst's saw 

 mill. The mill was intended to supply all the wants of a new settlement. 

 It, therefore, could saw lath, shingles, scantlins, bearers, and in short all 

 the forms of lumber used in raising the houses and workshops of a new 

 settlement. 



Mr. Seeley.— ^The feeding apparatus is the peculiarity. 

 Mr. Garvey. — -There is a peculiarity in the mode of adjusting the bed at 

 sight, so as to cut a thin or a thick board, or one tapering, being thick at 

 one end and thin at the other. Also, the log can bo put on centers so as 

 to saw the facets on the frustum of a pyramid of any number of sides, and 

 of any desired taper. This would be of use for preparing wooden pillars or 

 columns, giving an inexpensive mode of producing a nice architectural 

 effect. 



This saw mill costs about $450, and requires from 8 to 12 horse power to 

 work it at full work. 



Mr. Seeley.— This machine is desirable, as it enables a man to prepare 

 all the lumber he requires for building, but where several machines can be 

 worked it would not be as economical as the ordinary mills. It is always 

 best, when possible, to have a division of labor, and let one mill saw laths 

 only, another shingles, and another heavy lumber. This mill is intended 

 only for use in new settlements where regular saw mills are not already 

 established, and there it would, no doubt, be useful. 



Mr. Hoagland exhibited some specimens of the mineral paint alluded to 

 on the last evening. It is found m New Jersey, near New Brunswick, in 

 an old mill pond. It is formed by the decomposition of the rocks of the 

 locality, but evidently has some oxyd of iron in it and a quantity of decom- 

 posed vegetable matter. It is free from grit, and is fine enough for mixing 

 with oil as it is obtained from the pit. When the bed of mineral paint is 

 pierced with a stick a considerable quantity of gas escapes from it. 

 Dr. Stevens. -^What streams fall into this pond? 



