128 



Pruflun blue, 

 and fal ammo- 

 niac. 



Few injurious 

 to health. 



Caution to 

 magiftrates. 



They fhouM not 

 Jiften too readily 

 t© complaints. 



INJURIOUS MANUFACTORIES* 



ought to be confined to directing fcience toward the means oF 

 improvement of which thefe proceffes are fufceptible with re* 

 gard to health. 



The fabrication of Prufiian blue, and the extraction of car* 

 bonate of ammonia by the diftillation of animal fubftances in 

 the new manufactories of fal ammoniac, produce a large 

 quantity of fetid vapours or exhalations. Thefe exhalations, 

 it is true, are not injurious to health; but as it is not fuflieient 

 lo conftitute a good neighbour, not to be a dangerous one 

 merely, but not even to be a difagreeable one, they who un- 

 dertake fuch manufactures, when they have to feek a (ituation 

 for them, mould prefer one remote from any dweiling-houfe. 

 But when fuch a manufactory is already eftablilhed, we would 

 be far from advifing the magiftrate to order its removal: it 

 would be fufficient in fuch cafes, to oblige the manufacturer to 

 build very high chimneys, that the difagreeable vapours pro- 

 duced in thefe operations may be diffipated in the air. This is 

 particularly practicable for the fabrication of Pruffian blue, and 

 by adopting it one of our number has continued to retain in 

 the midft of Paris one of the moft important manufactories of 

 this kind we have, againft which the neighbours had already 

 leagued. 



. In the report we lay before the clafs we have thought it our 

 duty to attend only to the principal manufactories, againft 

 which violent clamours have been raifed at divers times and 

 places. It is eafy to fee, from what has been faid, that there 

 are but few the vicinity of which is injurious to health. 



Hence we cannot too ftrongly exhort thofe magiftrates who 

 have the health and fafety of the public committed to their 

 charge, to difregard the unfounded complaints, which, too 

 frequently brought againft different eftablifhments, daily threat- 

 en the profperity of the honeft manufacturer, check the pro- 

 grefs of induftry, and endanger the fate of art itfelf. 



The magiftrate ought to be on his guard againft the pro- 

 ceedings of a reftlefs or jealous neighbour; he mould carefully 

 diftinguifh what is only difagreeable or inconvenient from what 

 is dangerous or injurious; he mould recollect that the ufe of 

 pit-coal was long prefcribed, under the frivolous pretence that 

 it was injurious to health; in (hort, he mould be fully aware 

 of this truth, that, by Iiftening to complaints of this nature, 

 not only would the eftabli foment of feveral ufeful arts in France 



be 



