35G TRANSACTIONS OF THE AMERICAN INSTITUTE. 



vicinity was found saturatod with oil. From tliis statement it would be 

 infened that tlie upward force of the oil was nearly strong enough at tliat 

 point to form a natural spring, and only required the removal of a certain 

 quantity of the soil to set it in motion. 



With regard to the process of distilling the oil, he wished to add that the 

 specific gravity of crude petroleum is usually about 90deg, Baume; the oil 

 refined has not quite half that gravit3^ In addition to the lighter products 

 expelled by heat, there is a heavy residuiun which will, by re-distillation, 

 produce paraffine, a white substance used in the manufacture of candles, 

 which are harder than spermaceti and can be used in the warmest climates- 

 Mr. T. D. Stetson explained a method which had been recently patented 

 for preventing the oil from evaporating through the pores of wooden casks. 

 This is done by coating the inside of the barrel with an alkaline solution, 

 such as hot soap suds; and to prevent the evaporation of this alkaline 

 preparation, the outside of the l>arrel is covered with a lixed oil. This is 

 said to remedy a very serious difficulty in the transportation of petroleum. 

 After remarks b}' Mr. Minthorne and several other gentlemen, the Asso- 

 ciation selected "Preservation of Fruits" as the subject for the next regu- 

 lar discussion, and adjourned to Thuisday evening next. 



American Institute PoLVTEcnxic Association, ) 

 Sepfember 2'2d, 1864. ) 



Chairman, Prof. S. D. Tillman; Secretary, B. Garvey. 

 The following interesting items of scientific news were read by the 

 chairman: 



Esculent Nests. 



Dr. Calvert, of London, in a recent lecture on "Chemistry applied to the 

 Arts," says these curious gelatinous products are not only cinsidered great 

 delicacies in China and India, but even in Europe, where they realize from 

 'fifteen to thirty-five dollars per pound. It has long been consideied a 

 disputed question what is the chemical nature of the substances composing 

 these nests, which are the product of a peculiar kind of swallow; but Mr. 

 Payen, by his recent researches, has left no doubt in the minds of Chemists 

 that it is animal, not vegetable, matter. In fact, it is a peculiar mucous 

 substance secreted by the bird, and composed of carbon, hydrogen, ox'ygt!»» 

 nitrogen, and sulphur. P'urther, it is inscduble in ccld water, but soluble 

 in boiling, and difiers from gelatine and isinglass in that it does not gela- 

 tinize as it cools. 



Respiration of Flowers. 



M. Cahours gives in the Complcs Rendus tiie following summary of the 

 results of his researches: 



1. Every flower having odor or not, in a limited space of normal air, 

 inhales oxygen and exhales carbonic acid gas in variable proportions. 



2. Under like circumstances, the proportion of carbonic acid increases 

 with the temperature. 



