Injurious Manufactories . 31 
disagreeable to their neighbours. For certainly the em- 
ployments just named are more unpleasant to live near 
than the manufactories mentioned above, and the only 
advantage they enjoy is that of ancient practice. This 
right of toleration has been established by time and ne- 
cessity ; let us not doubt therefore, but our manufactures, 
when grown older and better known, will peaceably en- 
joy the same advantage in society ; in the mean time we 
are of opinion, that the class ought to avail itself of this 
circumstance, to put them in a particular manner under 
the protection of government, and declare publicly, that 
the manufactures of acids, sal ammoniac, Prussian blue, 
sugar of lead, white lead, starch, beer, and leather, as 
well as slaughter-houses, are not injurious to the health 
of the vicinity, when they are properly conducted. 
We cannot say as much for the steeping of hemp, 
making catgut, laystalls, and in general establishments 
where a large quantity of animal or vegetable matter is 
subjected to humid putrefaction. In all these cases, be- 
side the disagreeable smell they exhale, miasmata, more 
or less deleterious, are evolved. 
W e must add, that, though the manufactories of which 
we have already spoken, and which we have considered 
as not injurious to the health of the neighbourhood, 
ought not to be removed, yet administration should be 
requested to watch over them strictly, and consult with 
well-informed persons for prescribing to the conductors 
the most proper measures for preventing their smoke and 
smell from being diffused in the vicinity. This end may 
be attained by improving the processes of the manufac- 
tures, raising the outer wails, so that the vapours may 
not be diffused among the neighbours ; improving the 
management of the fires, which may be done to such a 
point, that all the smoke shall be burnt in the fire-place, 
or deposited in the tunnels of long chimneys and main- 
