Brass'^ 
114 
Tinning Copper.— The common method of tinning 
copper vessels, is first to scrape the inside clean from any 
rust ; then to rub them with sal ammoniac ; or while 
warm with rosin or fat : then melted tin is poured on the 
copper and by means of a cloth whitened with whiting 
to prevent the hot tin adhering to and burning it, spread 
evenly over the surface of the copper, and then planished. 
The common tin used for this purpose is usually adul- 
terated with lead which has been supposed to be very de- 
leterious, but some French experiments on the subject 
have shewn that it is less so than was imagined. 
The following papers on the subject of tinning copper 
vessels are worth noticing. 
New Process for Tinning Copper and other vessels in a 
durable manner . 
That copper and brass vessels cannot be used with 
safety in cooking victuals or for holding articles of food, 
and particularly those which contain acids, is well known. 
It is also well known that the tinning applied in the usual 
manner is not durable, being soon worn away by cleaning, 
and on that account must be frequently renewed. Some, 
therefore, have proposed enamelling for kitchen utensils 
of copper; which, indeed, would answer exceedingly 
well, and be much safer for the health than impure tin 
mixed with lead, often employed for tinning ; but, un- 
fortunately, enamel is too dear, and readily breaks when 
the vessel receives the least blow ; which cannot always 
be avoided.^ 
* Articles that would come high when made singly, may be af- 
forded at a low rate when manufactured on an extensive scale.— 
Cooking utensils lined with a vitrified glazing, are now common- 
ly sold in many shops in London, and at a moderate price. It 
would be as reasonable to object to the use of earthen-ware or Chi», 
na, because they may be broken by blows, as to make this an ob- 
jection against the use of glazed kettles. 
