Vol. XXV. No. 7.J 
POPULAR SCiENCE NEW^. 
99 
pails — therefore would uot be worth eight cents 
a pounJ. For parts of machinery where strength 
is required, weight for weight, it is not as strong 
as iron. As such iron can be bought for fourteen 
cents a pound, aluminium would be worth less 
than that; for the same strength, aluminium 
would be four times more bulky. For spoons 
and knife-handles, where no particular quality 
except looks is called for, it might be worth as 
much as tin — say twenty-two cents a pound. The 
drawback in tliat use would be its great softness, 
as it soils the fingers when handled, like lead. 
The only use for which, at present, pure alumin- 
ium may take, with advantage, the place of longer 
known metals, is for electric appliances and wires. 
For the same diameter, aluminium is twice as good 
a conductor as iron; its weight is almost exactly 
one-third, but its strength is only one-fourth, 
so that the wire could only be stretched three- 
fourths the distance over which iron wire is now 
stretched to 'keep the same relatiou between 
weight, strength, and sagging. For these pur- 
poses aluminium might be worth twelve cents a 
pound. It could be made harder by alloying it, 
I specially with silicon; but even the hardest alu- 
minium — short of aluminium bronze, which is 
essentially ninety per cent, copper — I met with 
was only about the strength of brass. The alloys 
of aluminium have all been made and tried thou- 
-auds of times, but no value has been found in 
tlieni which would make the aluminium worth 
more than copper — say, perhaps, eighteen cents a 
pound. The aluminium bronze keeps fairly bright, 
t)ut when made in its proper proportion is ex- 
tremely hard to work. In this bronze aluminium 
shows at its best, but does not come up to good 
steel in ease of handling and working. One ad- 
vantage is that the bronze is elastic and springy, 
even when almost red-hot. It consists essen- 
tially of ninety per cent, copper and ten per cent, 
aluminium. How much the metal is worth for 
advertising medals, for plaques, and other uses of 
a more sensational character is, of course, impos- 
sible to estimate. Its value ranks with that of 
the chromo. At present its greatest use lies in 
the magnetic power which it has for greenbacks, 
;uid in proving the defective experience of capi- 
talists. While, therefore, as will be seen from the 
liequent examples quoted, the true value of alu- 
minium does not lie much above that of zinc, 
which costs "six cents a pound, the cheapest alu- 
minium in the market is held at ■?!2.25, and the 
manufacturers are already compelled to send out 
circulars, in which you may read between the 
lines : 'Tell us some use of aluminium." There is 
not a single application, at present, in which alu- 
miuiuTn ranks intrinsically above the value of the 
same weight of copper, which is sixteen cents a 
pound. Even chemically it has not the energy of 
sodium, potassium, or magnesium, and in an ex- 
tensive practice as a chemist I haven't had a sin- 
gle use for aluminium in fifteen years." 
[Engineering and Mining Journal.] 
PREl'ARATIO.V OF THE OXIDES OF THE 
RAKER ELEMENTS. 
The use of the oxides of the rarer- elements in 
the various systems of incandescent gas lighting 
which are now coming into prominence, makes it 
of interest to note the manner in which these are 
prepared. Thorium, lanthanum, cerium, and di- 
dymium are obtained from the mineral monazite. 
This is, however, a complicated ore, and difficult 
to deal with. Orthite is another source from 
which cerium and didymium are obtained, the 
mineral costing in England about twenty-five 
cents per kilogramme. Zircon, from which zir- 
conia is obtained, was quoted some time ago at 
$1.8714 per ounce, but can now be bought in quan- 
tity at about fifty cents per pound. A similar re- 
duction in price has taken place in the case of 
thorite, from which thorium oxide is extracted. 
This mineral, as commonly obtained, carries about 
fifty per cent, thoria, ten per cent, uranium ox- 
ide, and fifteen per cent, silica. Yttrium is ob- 
tained from the mineral gadolinite. Most of these 
minerals are said to come from Norway. 
In the extraction of the oxides from thorite, the 
mineral is finely powdered and dissolved in hydro- 
chloric acid, with which it forms a stift' gelatinous 
mass, part of the silica passing into solution, which 
is evaporated to dryness to render the silica insol- 
uble. Hydrochloric acid is then added, and tlie 
chloride solution separated from silica, etc. Sul- 
phide of sodium is added to separate lead, etc., 
after which hyposulphite of soda is added to the 
dilute solution to precipitate all the thorium as 
the hyposulphite, most of the impurities passing 
into solution. Afterward, if necessary, the ce- 
rium, etc., are separated by bringing down first 
of all with ammonium oxalate from the solution 
of the chloride. 'ITie hyposulphite is dissolved in 
hydrochloric acid and then further precipitated as 
a hydrosiilphite for the second or third time. 
Finally, the thorium is brought down from the 
solution of the pure chloride with ammonia, thus 
getting a hydrate from which any of the other 
salts can be obtained. Zircon can be treated in 
the same way if first fused with bisulphate of 
soda or caustic soda, and afterward evaporated to 
dryness, the chemical reactions being much the 
same as in the case of thorium. Cerium may be 
prepared from cerite or the other minerals men- 
tioned of which it is a constituent. With the 
exception of zircon, most of the minerals, being 
hydrated silicates, are very soluble in hydrochloric 
acid unless they are first heated, in which case 
they become quite insoluble, excepting in boiling 
sulphuric acid. 
These oxides are recovered from the old and 
broken mantles, used in the incandescent gas 
lighting systems, in the following manner: They 
are first treated with sulphuric acid, evaporated 
to dryness, and dissolved in water. The solution 
of the sulphates is treated with caustic soda and 
the precipitated hydrates washed to get rid of the 
soluble sulphates. The hydrate is then dissolved 
in hydrochloric acid and treated with hyposul- 
phite of soda to precipitate the thorium and zir- 
conium. Lanthanum, yttrium, and cerium are 
thrown down from the filtrate as oxalates by am- 
monium oxalate. These oxalates are then ignited 
and dissolved in dilute nitric acid, by which means 
the cerium oxide is left undissolved, the lantha- 
num and yttrium oxides passing into solution. 
Another method, and one more useful in analysis, 
is to treat the oxides of lanthanum, yttrium, and 
cerium with ammonium chloride, thus converting 
the lanthanum and yttrium into the soluble chlo- 
rides and leaving the cerium insoluble. 
SCIENTIFIC BREVITIES. 
Crystals of Platinum. — Professor Joly, of 
Trinity College, Dublin, announces in Nature that 
he has succeeded in producing small crystals of 
platinum by stretching ribbons of pure metal, 
sprinkling them with powdered topaz, and pass- 
ing an electric current through the metal until it 
is red-hot. In half an hour, if the metal is ex- 
amined under the microscope after removal of the 
topaz, it is found to have small and brilliant octa- 
hedral crystals adhering to the edges. Other 
forms alae occur. Professor Joly says that the 
cause of the formation of the crystals is that flu- 
orine is liberated at a high temperature from the 
topaz, which attacks the platinum, forming a flu- 
oride, which again breaks up, depositing the crys- 
tals. This reaction is similar to what M. Moissail 
has already described. The same thing takes 
place with palladium. 
Sanguinite, a New Mineral. — II. A. Miers, in 
the Mineralogical Magazine, describes a new min- 
eral which has been named sanguinite. It was 
observed on specimens of argentine from Chanar- 
cillo, and is probal)ly ii hexagonal sulpharsenite of 
silver, allied to proustite. To the naked eye the 
mineral appeared to be gothite, but examination 
with the microscope revealed its difterent charac- 
ter. It has luster, like earthy hematite; color, 
bronze-red by reflected light, and blood-red by 
transmitted light; streak, dark, purplish brown. 
No quantitative examination was made, on ac- 
count of the small quantity of material ; a quali- 
tative analysis, however, showed the presence of 
silver, arsenic, and sulphur. The physical char- 
acters, as a whole, prevent the mineral from being 
referred to proustite or xanthoconite, the mineral 
being nearw like the former in its physical char- 
acters. The specific gravity and hardness have 
not been determined. 
Oil and Vinegar Mi.xture kor Domestic 
Use. — Hugo Niirdlinger, of Stuttgart, has hit 
upon a permanent combination of oil and acetic 
acid which is of great practical use for technical 
or medicinal as well as for domestic culinary pur- 
poses. It may be employed for preserving, or for 
making salads or mayonnaise. It is prepared in 
the following manner : Take olive oil of the best 
quality, and add to it, under constant and active 
stirring, some of the best cider vinegar. The pro- 
portion between oil and vinegar is not mentioned, 
but, as will be seen directly, it can readily be de- 
termined at the first trial. The turbid mixture 
produced is now mixed with finely powdered table 
salt and again thoroughly stirred, after which it 
is set aside to separate into two layers. The 
upper one will be perfectly clear and consist of 
oil combined with anhydrous vinegar or acetic 
acid, while the lower, turbid layer will contain 
water, salt, etc. The oily layer is decanted and 
bottled. The amount of stilt added is proportion- 
ate to the amount of water present in the mixture. 
If acetic acid is used, only a small amount of salt 
is wanted ; if vinegar is used, more must be taken. 
A New Storage Battery. — In a paper read 
before the Wisconsin Electric Club, at Milwaukee, 
Professor Haskins, of New York, described a new 
form of storage battery invented by Professor 
Main, of Brooklyn. This battery dift'ers from all 
others in the manufacture of the lead plate. He 
puts between two thick lead plates, say twenty 
sheets of very thin lead foil, like sheets of paper. 
Each of these thin sheets is covered on both sides 
with fine plumbago. The thick sheets on the out- 
side are like the covers of a book, of which the 
thin sheets are the leaves. The whole is then 
made solid by numerous lead rivets through the 
mass. The book is then punched, by a press, 
with numerous holes, entirely through. When 
this is done the plates are put into cells, and 
treated for weeks, until all the thin sheets are 
converted into active material. Of course the 
surface exposed to action is the circumference of 
these perforations. This forms the positive plate 
of the battery. The negative plate is a slab of 
amalgamated zinc, resting in a pan of copper, also 
amalgamated. The plates are horizontal, one 
above the other, in the jar. The chemical action 
is substantially the same as where two lead pipes 
are used. 
