EVAPORATING RANGE. 99 
B, C, D, placed in a descending range, the pan A being 
the highest in the series. The first three are stationary ; 
the fourth, D, is movable on a horizontal axis. They are 
constructed of sheet copper, or iron with wooden sides. 
When of the last-mentioned materials, both surfaces are 
protected by a heavy coating of iron paint.* Pans with 
bottoms of galvanized iron are furnished to order, but the 
zine coating is not preferable in any respect to either the 
plain or the painted iron surface, and is more expensive. 
The furnace should be of brick-work, of a uniform inside 
width throughout, corresponding to the width of the space 
between the abutments in division A. Each pan of the 
series is set perfectly level, but no two of them are in the 
same horizontal plane. The fall from B to C in a range of 
medium length should not be less than ten inches; from A to 
B and from C to D, two inches each.+ The furnace is suffi- 
* The advantages of this paint, iron minium, or brownish-red oxide 
of iron, “are its solidity, durability, cheapness, and above all, its prop- 
erty of preserving the iron completely from oxidation, and of harden- 
ing thewood. . . . Itis destined to supplant red-lead (lead minium) 
and other pigments that have been used until now for coating wood, 
iron, and other metals. It forms a smooth and stripeless coat upon the 
iron, varnishing as it were the metal and preventing the atmospheric 
influences upon the paint. . . . Iron minium mixes readily with 
other colors, such as black, yellow, green, etc., and by so doing a variety 
of colors is obtained to the convenience of persons who would not like 
the dark-brown of the iron minium paint. It has been proved by exper- 
iments that the iron minium paint lasts twice, and even three times as 
long as red-lead paint. . . . It resists generally the strongest heat. 
It is to be applied in several layers: the first ought to be thin, 
the second a little thicker. It is employed the same as other paints, with 
boiled or unboiled linseed oil. If unboiled oil is used, litharge or any 
good siccative may be added, but not turpentine.”—(Condensed from 
London Practical Mechanics’ Journal im Scientific American, vol. xi. 
p- 387.) 
{ Printed directions for setting up the apparatus are given on another 
page. 
