492 PHILOSOPHICAL TRANSACTIONS. [aNNO I767. 



j^n expeditious Method of making Nitrous jEther hy Distillation, without 

 Fire. — (See fig. 5.) Pour 6 oz. of the most concentrated spirit of nitre, little 

 by little, on 8 oz. of rectified spirit of wine, shaking the vessel each time in 

 which the mixture is made. Then convey it by a long funnel through the 

 opening of the head at c, into the matrass a; the opening is afterwards secured 

 by a glass stopper; in warm weather this mixture grows hot in 5 or 6 minutes, 

 and distils in a stream into the vessel e, and is over in about half an hour. Before 

 the matrass grows cold, a fresh mixture is put in as above, and so on for 5 or 6 

 times, till there is liquor enough distilled. This liquor being slowly rectified 

 with slacked lime, makes very fine aether. The spirit of wine, which was put 

 into the vessels e and p, to condense the vapours, is so highly charged with 

 sether, that it will separate on washing with water. This spirit of wine is also 

 an exceeding rich spiritus nitri dulcis. What remains in the matrass, contains 

 a quantity of spirit of wine, which may be separated by distillation. 



On the Distillation of the Nitrous Acid ; see fig. 1. — The quantity that is 

 condensed in water, during the distillation of this acid spirit, is so small, that 

 it would be scarcely worth saving, if it was not to prevent those noxious fumes, 

 which have such an effect on the lungs of the operator, as frequently to make 

 him spit blood. Water highly charged with these fumes by repeated distillations 

 becomes blue, and retains its colour.* Mr. W. once distilled, in an iron body 

 with a stone head, 30 lb. of nitre, with 6o lb. of green vitriol, which he had 

 calcined to whiteness, and was obliged to make use of two vessels of water, as in 

 fig. 5, at F and g, to condense the vapours: this water became blue in one 

 distillation, and continued so for J 8 months, till he made use of it. A great 

 quantity of air was set free from the beginning to the end of the distillation, 

 owing in a great measure to the acid fumes acting on the iron body; for if 

 distilled in a glass or stone vessel, the quantity of air is not near so considerable. 

 The nitrous fumes condensed in water, in making the spiritus nitri fortis, appear 

 to be more acid than the strongest oil of vitriol made use of for the experiments 

 on spirit of salt. Water is not heated by these fumes; owing probably to the 

 smallness of the quantity which condenses in it. 



A further Application of this New Method of Distillation. — In the distillation 

 of the oil of vitriol, a great part of the acid comes over sulphureous, and is 

 very hard to condense; but, by passing it through water, this condensation is 



• Oil of vitriol was used in this operation, to set free the acid of nitre; and Mr. W. found 

 on trial the fumes condensed in the water to be a pure spirit of nitre ; whereas, in the other 

 operation, where calcined vitriol or copperas was used, the fumes contained some acid of salt. This 

 led him to try the common green copperas, and he found it contained a portion of iron united 

 to the acid of salt: whereas the Dantzic copperas, or vitriol, contains no acid of salt, and iherefore 

 is fitter to make an aquafortis for the refiners' use. — Orig. 



