68 
THE CHIGWELL ROW MEDICINAL SIRING. 
when it did not operate this way, it did by urine ; and w d at 
first occasion sickness and make her reach once or twice about 
an hour after taking it. 
I drank half a pint of it myself for several mornings. It 
gave me at first a kind of uneasiness and sickness for an hour 
or more, as if it wanted to pass off or come up again, but it 
did not. I increas’d the dose to near a pint. This found its 
way and purged me two or three times a day moderately and with¬ 
out griping or any uneasiness. I decreas’d the dose again and 
found a little more than half a pint w d keep me regular once a 
day. It seem’d to give me spirits and appetite. I continue 
it at times and always with the same effect. 
I order’d a countryman (from some place near Collier Row) 
who ask’d my opinion upon a very obstinate erysipelatous 
humour in both legs to drink a full pint every morning for 3 
weeks or a month ; but he came to thank me at the end of the 
fortnight, quite well and in great spirits. 
From the manner of the operation of this water and the ex¬ 
periments I have try’d to discover its analysis, I am of opinion 
it is a compound, being a chalybeate extinction 22 and a nitrious 
salt blended together. Two grains of Alleppo Galls, finely 
powdered, strew’d upon the surface of 16 oun 8 of this water, 
gave a dark purplish colour inclining to black, but soon 
became turbid ; but, by standing about 14 hours, it pretty nearly 
recover’d its first clearness and complexion, and a reddish ocrey 
sedim 1 precipitated to the bottom. If a few drops of oil of 
vitriol be added, it will become clear as at first, without any pre¬ 
cipitation : from hence, I conclude the dark purplish colour is 
effected by alkali salts united to the acid. That the salt of 
this water is rather of a nitrious kind appears plain to me from 
its turbidness, and more so from its precipitation, which sp* of 
vitriol prevents, tho’ it destroys the colour. Upon its standing 
quiet for some hours, there arises a fine film or scum upon its 
surface, reflecting different colour’d lights, as upon lime water ; 
w eh is pretty comon to all chalybeate waters, and w ch may 
probably be occasion’d upon the seperation of the nitrious and 
vitrioline parts by y e air. 23 Scarbro’ water discovers the same 
22 “Extraction” is. perhaps, meant. 
23 Mr. Dalton writes:—“By ‘nitrious' must not be understood any nitric or nitrous 
*' compounds, although the former might be present in small amount. From the context, the 
“term ‘nitrious’ may be supposed to be used ior the sulphate of magnesia, resembling 
■“nitre in some external aspects. The oxidation of the iron tannate into ochre would result 
