[834] 
by the Epfom Salt, where the Terra akaltna Salts 
communis , joined with the Acidum vitriolicum ; and 
after the fame manner in the Salmirabile , the alcaline 
Earth caufes the bitter Tafte. The fame may alfo be 
found, by mixing Quick-lime with Spirit of Vitriol, 
and it will produce a very bitter Tafte j but the Mix- 
ture of Quick-iime with Spirit of Nitre caufes a Bit- 
ternefs which exceeds Gall. 
One Pound Troy of this Water yields 29 Grains of 
the faid Sal medium^ and 3 Grains of the Earth. 
Remarks by C. M. 
The Right Honourable the Lord Cadogan had communicated a 
fhort Account of thefe Waters to the Royal Society on April 17. 1735. 
being a Letter his ILordfhip had received from Mr. Tho. Dundafs, Sur- 
geon to his Lordfhip’s Regiment, dated at Gloucefler , March 25. 1735-. 
wherein he gives an Account of fome few Experiments he had made 
on thefe Waters, vVhich moftiy agree with the preceding ones 3 as 
that there were no Marks of a Chalybeat Nature in them 3 nor any 
Signs of Nitre or Sulphur : But that fix Quarts of this Water being 
diflilled very carefully, the Sediment at the Bottom of the Veflel was 
nothing more than Alim and Sal Gem-, to which it owes its purgative 
Quality. Some of the Salt of this W ater, being put into a Solution of 
Silver, quickly made a Precipitation of the Silver. Mr. Dundafs fays, 
that fome alcaline Liquors, as Oil of Tartar , Spirit of Sal Ammoniac , 
&c. being dropt into fome of the Water, immediately produced a 
violent Effervefcence 3 which plainly fhews a great Acidity 3 which be 
afcribes to the Alum in this Water. M. Sevckenherg found no fuch 
Effervefcence on mixing thefe two alcaline Liquors with the Water 3 
but only fays it grew milky, and a little white Precipitate fubfided. I 
can account for this material Difference no otherwife, than by fuppofing, 
that the Acid, which caufed the Effervefcence in Mr. Dundajs’’ s Expe- 
riment, was a volatile Gar, which was not quite fpent in being carried 
no farther than Gloucefler , but which was quite evaporated and flown 
away before the Water came into M. Senckenberg’s Hands in London : 
And as to the Alum , M. Senckenherg did not attend to it. 
iC Mr. Dundafs thinks thefe Waters may be of Ufe in a lax Confti- 
<c tution 3 when the Humours are of an alcalefcent Nature 3 but, when 
t£ acefcent , muff do Hurt. ” 
XXII. An 
