96 
Not one dispenser has succeeded in making the prescrip- 
tion to the exact strength in either the mixture or lotion. 
In the potassium iodide mixture, five out of the eighty- 
one dispensers have come within the range of \ a grain 
more or less than the prescribed amount ; forty have made 
the strength of the mixture within 5 grains more or less 
than the prescribed amount ; whilst the remaining forty-one 
have made greater errors. 
In the zinc sulphate lotion fourteen out of the eighty- 
one dispensers have come within the range of J a grain 
more or less than the prescribed amount; forty-five have 
made the strength of the lotion within 2 grains more or 
less than the prescribed amount ; whilst the remaining 
thirty-six have made greater errors. 
It may be interesting, before leaving this part of the 
subject, to make a few further observations on the dis- 
pensing of these solutions. We found that the mixture of 
No. 74, dispensed by a man in Birmingham, was strongly 
alkaline to test paper, and I submitted its contents to 
further analysis and found, that out of the 115 7 grains 
represented in the table, 100*1 was composed of carbonate 
of potash, and 15*6 of iodide of potassium, etc. From 
this large proportion, it seems as if the former salt had been 
intentionally added, along with a small proportion of potas- 
sium iodide. One (No. 48) from Eccles contained 2*5 grains 
of Potassium Carbonate in the 126*7 grains weighed out. 
Many were absolutely free from Potassium Carbonate and 
many contained traces of that salt. No. 46 had both the mix- 
ture and lotion corked with very dirty corks. The dispenser 
of No. 16 (from Edinburgh) put in a preparation of orange 
