PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION. 399 



tapping. For charcoal, as T have said, we have other trees that grow much 

 faster. On the whole, I would not advise its extensive cultivation. If I 

 had a large forest of trees and intended to destroy them, I should not hesi- 

 tate to tap them. I certainly should take away their strength. I should 

 also consider it unwise to go in to this sugar business singly. It should 

 be done on a large scale. Companies of the farmers should be formed, and 

 they should concentrate their efforts in order to make it profitable. Thia 

 Institute might be the source of valuable information to them. And now, 

 since the Transactions of the Institute are to be placed in every school dis- 

 tinct in the State, it is very important that we should furnish them with the 

 results of experiments, and thus save them from embarking in useless and 

 unprofitable undertakings. 



The Chairman. — It is well known that the chemist can make sugar from 

 saw dust by means of sulphuric acid; and there are various other substances 

 from which it can be made. Doubtless, a practical application of scientific 

 knowledge in the selection and use of new substitutes for the cane will lead 

 to very important results. It is desirable every farmer should understand 

 whether it is best to boil the syrup and make the sugar on the farm or send 

 the liquid product to the manufacturer. 



Mr. Dibbin. — I consider the best way for the farmer is to sell his syrup 

 to the manufacturer, and avoid purchasing those machines that are so nu- 

 merous in the country for making sugar. It can be done better and cheaper 

 by the regular sugar maker, as is manifest when we consider the facility 

 and reduced cost at which articles can be manufactured on a large scale. 



Dr. Rowell. — The wood that grows very rapidly makes a very poor char- 

 coal. The maple, being a hard wood, is valuable for this purpose. 



Mr. Veeder. — Some of the softer woods, such as the Lombardy poplar 

 and the ash, make a very good charcoal, 



Mr. Rosevelt. — In France they use charcoal not much thicker than the 

 finger, made of hard branches, and it is considered very good. 



At the suggestion of the chairman, the subject of Horology was selected 

 for discussion for the next meeting. 



Adjourned. 



American Institute Polytechnic Association, ) 

 May 2Ut, 1863. j 



Cbairmau, S. D. Tillman, Esq; Secretary, Mr. John W. Chambers. 



Root's New Steam Engine. 



Mr. John B. Root presented a model of his new duplicate steam engine, 

 a workit'g model of which is in operation at the works of Mr. J. L. Jackson, 

 28th street, N. Y. Mr. Root made drawing's on the blackboard, showing 

 its peculiar structure. It has two rectangular pistons working at right an 

 gles. The inventor showed the mode of reversing. The steam can be cut 

 off at half stroke, and the exhaust kept open until the end of the stroke, 

 After being a little used, and the surfaces get to a bearing, the wear is very 

 little, and it does not seem to be affected by expansion, as all the parts are 

 heated alike, and not like other rotary engines, where the steam acts only 



