320 SCIENTIFIC NEWS. 



rupj and set aside to crystallise. In eight days It was converted 



into a crystalline mass, having nearly the sensible properties 



Afforded sugar of common brown sugar mixed with a little treacle. The 



equal to one • , r i i . , ^ . , 



Seventh part of ^^'^'g"*^ °f the saccharme matter thus obtained from eight 



the weight of pounds and three quarters of potatoes, and which I conceive to 



be intermediate between cane sugar and grape sugar, weighed 



one pound and a quarter. 



One pound of this crystallised saccharine matter was now 

 redissolved in four pounds of distilled water, and by the ad- 

 dition of a quarter of an ounce of yeast submitted to alcoholic 

 fermentation. In ten days the temperature having varied from 

 44" to 54o, the smell of the liquor first indicated that the 

 alcoholic fermentation was just beginning to pass into the 

 acetous. The whoJe was then instantly submitted to distillation, 

 and the process continued till a pint and a half of fluid was 

 collected in the receiver. This on being redistilled produced 

 two ounces and five eighths by measure of dilute alcohol, of 

 which a cubic inch, the mercury in Fahrenheit's thermo- 

 meter standing at 45° and in the barometer at 221.^ inches, 

 weighed 245 grains. I have therefore concluded from the 

 accurate experiments of Sir Charles Blagden, that ihe two 

 ounces and five eighths of dilute alcohol thus obtained con- 

 5* tains fourteen drachms by measure of proof spirit. 



I am, dear Sir, very truly your's, 

 Oc^^fr 25, 1812. G, L. TUTHILL. 



Soho Square, 



SCIENTIFIC NEWS, 

 New Explosive Compound. 



Notice has been received from the Continent of a newexplo* 

 sive compound, upon which Sir Humphrey Davy has made some 

 experiments ; and it has also been produced by others. The 

 present short statement is all that I can on this occasion insert. 



Nitrate of ammonia is to be dissolved to saturation in water, 

 and exposed in a basin to a low temperature, such as that of 

 ice, or rather the freezing mixture of ice and salt.— A vessel 

 containing oximuriatic gas is then inverted in the solution. 

 The^ gas becomes absorbed, and the solution ascends ; and, 

 after one or two hours, a small portion of heavy oil is found 

 at the bottom of the basin. Of this oil if a quantity of the 

 size of a pin's head be put into contact with olive oil, a violent 

 and dangerous explosion takes place. 



A friend who repeated this experiment, used a four ounce 

 phial of the gas and put his olive oil in a small platina 

 spoon. The spoon was destroyed by the explosion. 



