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periea.

The great objeAion has up to the present time been its
cost, but I am informed that this has now been so far
reduced as to bring it within the scope of extended com-
mercial use ; and, should it be used on a larger scale,
the price could be readily brought much lower.

Professor Doremus claims that the precipitation of the



calcium and magnesium salts takes place with very great
rapidity, that the sediment shows no tendency to cake or
adhere to the sides of a hot vessel, and that it is less
bulky than the precipitate formed by soda-ash.

In preparing sea water in the way I have proposed,
every precaution must be taken to add slightly less of the
precipitant than is necessary to entirely throw down the
calcium and magnesium salts, as it is manifestly impos-
sible in pradice to guard against small quantities of sea
water finding their way into the boiler either from leaky
condensers or else being fed in by the engineer during
some emergency, and, if under these conditions any
excess of the precipitant were present in the boiler, a
bulky precipitate would be thrown down and cause
trouble, although it would not bind into a solid scale.

There is no doubt that, if Professor Doremus can so
reduce the price of sodic fluoride as to enable it to be
used for this purpose, it would be of great use, as the
fluoride undoubtedly completes its adtion on the salts of
magnesium and calcium more rapidly and thoroogfaly
than the soda-ash, and it would be easier therefore to so
regulate the quantity added as to remove, say, five-sixths
of the injurious constituents from the sea water withoot
allowing any precipitant to enter the boiler.

In conclusion, I will briefly recapitulate the means
which seem to me best adapted for preventing the forma-
tion of the dangerous organic and oily deposits I have
considered in this paper, and these are : —

I.— Filtration of condenser water through a coke
column.

II.— Free use of the scum cocks.

III. — The use of water of considerable density rather
than of fresh water.

IV. — The use of pure mineral oil lubricants in the
smallest possible quantity.



THE PRECIPITATION OF MANGANESE AS

AMMONIUM MANGANOUS PHOSPHATE.*

By ALEXANDER G. McKENNA.

In the determination of manganese in iron ores, it is
customary to precipitate the manganese as dioxide, after
separation from the sesquioxides by the basic acetate pro-
cess, by adding bromine to the filtrate from the acetic
acid precipitation. The manganese thus thrown down
may be ignited and weighed as manganese proto-sesqui-
oxide, but the results are inaccurate from two causes.
Manganese dioxide when precipitated in the presence of
sodium or potassium salts always carries down with it
some alkali, which appears to be chemically combined with
the manganese, since it cannot be removed by the most
prolonged washing with water.f

This source of error can be avoided by using ammonium
acetate in the basic separation, but in this case the
solution must be made alkaline before manganese can be
precipitated by bromine, and the separation from calcium
18 then rendered less sharp.

Another objedion to the determination of manganese
based on the ignition of the precipitated dioxide is the
uncertainty of the resulting oxide, which is generally
assumed to be MosO^. Pickering^ has shown that the
percentage of manganese in this oxide varied between
69*69 per cent and 75 per cent, according to the tempera-
ture of ignition and other causes.

It is now customary to re-dissolve the manganese
dioxide in hydrochloric acid, and then precipitate it as
ammonium man^anous phosphate. The precipitate is
ignited and weighed as manganese pyrophosphate.
This method of determining manganese, which we owe to

♦ From the Technology Quarterly, Vol. iii^No. 4, November, 1890.
f See Wright and Meoke on Manganese Dioxide, in the Journal
of the Chemical Society for i8do, p. 23.
X Chbmical News, vol. zliii., p. 226.



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CamcALNiirt,!

April 17, 189X. f



Precipitation of Manganese.



185



Dr. Wolcott Gibbs, is now generally admitted to be the
most accurate aa well as the most easily performed of all
Ifae methods of determining manganese. It has been
▼arionsly modified by many chemists, but none of these
modifications seem to possess any advantages over the
original process as given by Dr. Gibbs.

The following work was undertaken at the suggestion
of Dr. T. M. Drown, to determine if some of the proposed
chan|^es in the details of the process were of any advan-
tage m simplifying the method or enhancing its accuracy.

Two solutions of manganous chloride were prepared,
and measured portions were taken for precipitation. In the
first method, Gibbs*s original direAions were followed.^
The precipitation was made in a platinum dish, by adding
a solution of sodium hydrogen phosphate in excess. The
white precipitate which formed was dissolved in hy-
drochloric acid, the solution heated to boiling, and am-
monia added in excess. The solution was now boiled for
ten minutes and allowed to stand near the boiling-point
for one hour. It was filtered hot, and washed with hot
water.

In the second method, Blair'sf diredionswere followed.
The solution was made acid with hydrochloric acid, an
excess of sodium hydrogen phosphate added, the solution
brought to boiling in a platinum dish, and ammonia added
drop bv drop, wiUi constant stirring, until further addition
of a drop of ammonia made no change in the silky
charader of the precipitate ; a dozen drops more of am-
monia were added, and after boiling a minute longer the
solution was cooled in ice water before filtering. The
wash water used was made by dissolving xo grms. of am-
monium nitrate in 100 c.c. of slightly ammoniacal
water.

The chief objed in view in the third method was to dis-
cover if there is any valid obiedion to making the precipi-
tation in glass, and also to determine the length of time
required tor complete precipitation. To the solution of
manganese salt in a beaker, hydrochloric acid and sodium-
hydrogen phosphate were added. The solution was
heated to boiling, and 20 c.c. ammonia water added. The
boiling was continued three minutes, with constant stir-
ring, which is absolutely necessary to prevent bumping.
The wash water used was made by adding one volume of
ammonia (sp. gr. o'gfi) to three volumes of water. Fol-
lowing are the results obtained in this series of
analyses :^

Compofison of Results Obtained by the Three Methods,



origi
method.
Gmsf.
Weight of manganese)

pyrophosphate ob-V "^^ «..SJ4

tined, first solution/ ^^^^ ^^^*

Do., second solution . . 0*0897 0*0896



Precipitation in

glAM and

'Mhiog wit

method, ammonia water.

Grms. Grmi,



0*4994
0*5007

0*0894



Three more determinations were made by precipitation
in glass, but the predpitates did not become crystalline
in Uiree minutes, and the washings were turbid.

The manganese precipitates after ignition were ex-
amined for silica, but none was found.

This set of experiments seems to show that essentially
the same results are obtained by following either Gibbs's
or Blair's diredions ; also that ^lass is not attacked by
the solution in three minutes' boiling, but that this time
is not always sufficient to ensure the complete conversion
of the precipitate to the crystalline form which is neces-
sary before filtration.

Another series of experiments was made in the same
manner, but with a different amount of manganese.

* Am, Jour. Sci., [II.], vol. xHv., 216.
t ** The Chemical Ans^s 6f IrOo," p. 93.-



Second Series of Results,



Weight of manganese
pyrophosphate ob-
tained •• •• ..



GibbB's
method.
Grroa.

0-2415
0*2427
0*2408
0*2432
0-2355*



Blair's In glass, as
method. before.
Grms. Grms.



0*2432
0*2432
02385



0*2412
0*2427
0*2425
0*2387*



* Not crysUlUne.



These results confirm those in the first series, and in-
dicate the necessity of having the precipitate thoroughly
crystalline.

The amotmt of manganese in the filtrates and washings
of each set of these experiments was determined (except
in those cases where the precipitate was not crystalline)
with the following results. The total volume of the filtrate
and washings was in each case about 300 c.c.

Solubility of the Precipitate,

Blair's method.
Gibbs's method. Washed with In glass.
Washed with dilute ammo- Washed with

water. niam nitrate, dilute ammonia.

Average grm. Average grm. Average grm.



Filtrate contained
metallic man-
ganese • . . .

Washings con-
tained metallic
manganese • .



0*0005



0*0005



0*0004



0*00x2



0*0003



In order to determine the relative values of the three
wash waters under precisely the same conditions, about
three times the usual amount of manganese was precipi-
tated by Gibbs*s method, and the precipitate was divided
into approximately equal parts by pouring alternately on
three filters. The precipitate in each filter was washed
thirty times, j c.c. of wash water being used each time.

The following results were obtained in two experi-
ments . —

Solubility of Precipitate, Second Series,

In In ammonia In ammoniam
hot water. (x : 4). nitrate.

Grm. Grm. Grm.

Washings contained f 0*0012 0*0019 0*0024
metallic manganese 1 0*0018 0*00x6 0*0014

These results show that, if there is any preference, it is
in favour of hot water.

On washing with ammonia water, the precipitate is
changed in colour to a dark gold, which change does not
occur with either of the other wash waters.

Another set of nine determinations was made in glass
by boiling the solution, with constant stirring, for eight
minutes, or until the precipitate seen through the walls of
the beaker had a peculiar silky appearance, resembling
that of mercurous chloride when precipitated from a
mercuric salt by stannous chloride. The precipitate was
washed with hot water.

Results of Precipitation in a Beaker and Washing^ with
Hot Water.

Grm. Grm. Orm.

Weight of manganese f 0*2450 0*2445 0*2450

pyrophosphate ob-'j 0*2445 0*2443 0*2445

tained ( 0*2440 0*2443 0*2442

No silica could be found in any of the precipitates after
ignition.

In one experiment iron was present in small amount
with the manganese. The precipitated phosphate had a
beautiful gold colour, and on being washed with dilute
ammonia dissolved gradually in the wash water, giving a
brown coloured filtrate. Continued washings showed no
diminution in the amount dissolved. On standing ex

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i86



Mixed Metals or Metallic Alloys.



fCRBMlCALlltWl^

I April 17, 1891.



posed to the air for several hours, a brown precipitate
settled out from the wash water. This would seem to
indicate the formation of some double salt of manganese
and iron, which is soluble in ammonia when an excess of
an alkaline^ phosphate is not present.

(Since tlie above was written, there has appeared in the
School of Mines Quarterly, Vol. xi., No. 4, a paper on the
same subjeA, by Mr. K. C. Boyd, which confirms, in
general, the results given above).



NOTICES OF BOOKS.

The Evolution of the Elements : a Sketch of a Biogenetic
Foundation for Chemistry and Physics. (Die Entwicke-
lung der Elements : Enturf zu einer biogenetic Grund-
lage fur Chemie und Physik). By Gustav Wendt.
Berlin : Hirschwald.
That elemental evolution — the necessary complement o^
our accepted interpretations of the phenomena of astro-
geny and organogenjp — has been for some time '* in the
air " is almost a truisip. The old theory of some seventy
odd simple bodies, all supposed primordial, independent
and incapable of mutual conversion, fails to satisfy the
inquirer. We crave to know how they have arisen ; why
their number and their mutual relations are as we find
them. Attempts have been already made to answer these
questions. The evidence in favour of the non-primordial
charader of the elements has been carefully marshalled.
A principle, the survival of the most inert, has been sug-
gested as likely to play a part similar to that of the
survival of the fittest in the organic world. The author
of the present memoir goes boldly forward. He contends
that the chemical elements are not present in all other
worlds in the same number as we find them at our feet.
It is not by accident that a certain number have met
together with us, another, e.g., on Mars, and some few
in the nebul». Each of the heavenly bodies has a number
of elements exadly corresponding to its present stage of
development. Or, as he otherwise puts it, the chemical
elements are gradually formed during the evolution of the
stars and planets. He raises the question whether it
might be possible here upon our earth to produce the
conditions for several atomic combinations of identical
atoms, and thus convert elements into each other. But
he does not reply in the affirmative. He suggests that
the art of making gold will probably never be learnt, but
perhaps some day iodine may be made out of bromine.

Herr Wendt even ventures to construe a genealogical
table of the elements, and to fix their possible number.
He considers that ** the elements in the earth have been
formed so that from the seven fundamental elements two
series each of seven elements have been gradually evolved,
and that further from each of the 3 x 7 elements a further
series is derived.'*

The fundamental elements are hydrogen, lithium,
glucinum, boron, carbon, nitrogen, and oxygen. The next
seven elements, fluorine, sodium, magnesium, aluminium,
silicon, phosphorus, and sulphur, form a second complete
series. Herr Wendt objeds to the pradice of placing
hydrogen alone as a quite exceptional element, and be-

gmning the first series of the elements with lithium. He
onbts the propriety of classing it as an eledtro-negative
element. lie obieds to several of the details of the
arrangement of the elements in the periodic system as
formulated by Mendeleeff and Meyer. Thus he transfers
chrome from the ** oxygen *' to the iron group, and pro-
poses to fill up the vacancy in the latter group by the
insertion of Websky*s ** idunium." The author protests
against the position attributed by Lothar Meyer to
copper, i.e., between sodium and silver. From a con-
sideration of its properties he transfers it to the iron
group.
The vacancy between sodium and silver he assigns to



Dr. Phipson's ** adiniom,** which, hitherto, like idunium,
has not been by any means generally recognised.

As regards the possible number of the elements, Herr
Wendt pronounces the maximum number, XXX2+2B79,
the minimum 74, and the mean about 77. Hence, it
would seem that he can scarcely accept the resolution of
didymium into neodymium and praseodymium, and still
less the highly complex (or mixed) charader of cerium
and others of the rare earths, to which, indeed, he makes
no reference. He considers that if the determinations of
Griinwald are found trustworthy on further extension this
savant will have rendered a morphology of the elements
possible.

WhiUt fully agreeing with the author as regards the
genesis of the simple bodies by a process of evolution, we
are not able for the present to accept his limitation of
their number. This point we should prefer to leave for
decision by the d posteriori method of spedroscopic and
micro-chemical research. Nevertheless, we think that
Herr Wendt*s work is entitled to the most careful study
of every chemist who is really concerned about a truly
rational development of his science.



Mixed Metals or Metallic Alloys. By Arthur H.
HiORNS, Principal of the School of Metallurgy, Bir-
mingham and Midland Institute. London : Macmillan
and Co.
The author begins his work with a historical intro-
dudion, a classification of metals, and some remarks on
their general properties. We regret having once more to
point out an erroneous atomic weight attributed to plati-
num, viz., 197*4. After a variety of other preliminary
matter, mostly of a very useful charader, Mr. Hioms
begins the study of alloys with the metallic compounds of
copper. Here he remarks that *' pure copper has never
been cast in considerable quantity so as to produce a
good dudile casting free from blowholes.'* An elaborate
account is given of the effed exerted upon copper by the
admixture of small quantities of other metals. An exten-
sive table shows the properties of recognised copper-zinc
alloys to the number of 144, showing their analytical
composition, specific gravity, colour, tenacity, dudility,
malleability, hardness, fusibility, and condudivity for
heat and eledricity. Under the last head many blanki
remain to be filled up.

Bronzes are next discussed in a very comprehenatre
manner, including a table of copper-tin alloys. The pro-
portion of phosphorus in phosphor-bronze must not exceed
4 per cent. A table published by the Phosphor- Bronze
Company is appended, with the remark that the absence
of the statement of the composition of the alloys robs it
of its chief value. Silicon bronze is considered superior
to phosphor-bronze in its eledric condudivity, and has
entirely replaced it for telegraphic purposes. Of the
aluminium bronzes, that with 10 per cent of aluminium
is considered the best.

As regards the alloys of tin and lead, the author
ventures upon the hazardous statement that an alloy
containing 18 per cent of lead is quite harmless in vessels
for wine and vinegar 1 The alloys of silver and steel
examined by Faraday and Stoddart do not present any
pradical interest. Mr. Hiorns may be congratulated upon
the fad that he has produced the best manual of alloys
to be met with in the English language.



Adion of Chlorine upon Metbylethyl Acetone. —
D. Vladesco. — It may be admitted for the present that
there are formed by the limited adion of chlorine upon
methylethyl acetone in the cold, two chlorine derivatives
— methyl-o-chlorethylcetone and methyl-a-dichlorethyl-
cetone. These derivatives are capable of giving rise to
bodies with multiple fundions, alcoholic and ketontc.
The author proposes to continue the study of these com-
pounds,^B«rtVA/# der Deutsch. Chem. Gisell., v. No* 3.



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April 17, 1891. I



Fellowship of Learned Societies.



187



CORRESPONDENCE.

THE FELLOWSHIP OF LEARNED SOCIETIES.

To the Editor of the Chemical News,
Sir, — I venture to ask that you will allow me to trespass
00 your space so far as to ofter some remarks on a subjed
that has lately given rise to no little controversy and
discussion among the Fellows of at least two leading
scientific Societies, viz., the Chemical and the Linnean.

To readers of the Chemical News it is of course well
known that it has, for many months past, been a subjeA
of complaint among the Fellows of the Chemical Society
that improper persons have obtained admission who have
no real interest at all in science, no qualifications en-
titling them to the honour of Fellowship, and whose only
objeA in joining was to obtain the powers of writing
F.C.S. after their names, thereby stamping themselves
among the lay world as qualified chemists ; and further-
more — turpisnme dictu / — using this assumed qualifica-
tion for trading purposes. We all know that this feeling
has given rise to some agitation among the Fellows, and
has brought on a mild epidemic of blackballing at the
ballots.

At the annual meeting Dr. Russell referred, at consider-
able length, to this controversy; and in a speech that, as
all must admit, abounded in good feeling and conciliatory
spirit, expressed his views to this effed : that the Fellow-
ship of the Chemical Society was not, neither was it
intended to be, any mark whatever of qualification ; that
the Institute of Chemistry was open to all who wished to
obtain a diploma stamping them as competent chemists,
whilst the F.C.S. signified nothing at all ; that so far
from being exclusive or insisting on evidence of qualifica-
tion he would wish to see the Society open to all —
including even mere amateurs — who might be desirous of
joining, always provided that candidates were personally
unimpeachable, and were not joining for the sake of
obtaining an F.C.S. to be used for trade purposes. In a
word. Dr. Russell— as I understand him — would make the
F.C.S. as meaningless and valueless as any evidence
of chemical knowledge as would be the '* Fellowship " of,
for instance, the Society of Arts.

Before discussing this position let me refer to the
Linnean Society. Here, too, a somewhat similar com-
plaint has been made, viz., that certain persons have
obtained the Fellowship simply with the intention of
advertising themselves as F.L.S. for trade purposes. It
was proposed at a recent meeting of the Linnean Society
to limit the number of Fellows annually eleded to 30,
with the objeA of eleding only the nK>st fit and proper
persons. This proposition (which was thrown out) gave
rise to a somewhat warm discussion ; on the one hand it
was contended— just as by Dr. Russell — that the Fellow-
ship was in no sense a diploma, or bad no academic
value ; that the Ro^al Society existed for the purpose of
honouring scientific workers, and that it was very
undesirable for any other Society to ere^ itself into a
quasi degree-granting body ; let the Fellowship be open
to all persons who wished to join, provided always that
they were personally unobje^ionable. On the other hand,
it was contended, inter alia, that the Fellowship of the
Linnean was an honour, and should not be lightly
lavished.

Having thus stated the quarrel may I — without incur-
ring the charge of presumption — venture to express a
criticism ? I cannot agree with Dr. Russell and others
that the Fellowship of such Societies as the Chemical
and the Linnean is not an honour or qualification. I
cannot admit that — always if merited — it is other than
an honour ; and it seems to me that it should be so

f ranted as to mark a man as possessing a competent
nowledge of chemistry or biology, respedively. That it
should possess any of the rigid precision of a London
degree I do not for a moment contend, but simply that



it should be given only to those who can show that they
have earnestly studied and acquired a thorough grounding
in the branch of science concerned. Neither can I follow
Dr. Russeirs argument that the existence of the Institute
of Chemistry precludes the Chemical Society from giving
any status by granting its Fellowship; and this, for two
reasons : firstly because the Institute of Chemistry, which
was founded in order to give every competently trained
chemist an opportunity of stamping himself with its
diploma, has persistently stultified itself by resolutely
refusing even to inquire into a candidate's knowledge
unless he have required that knowledge in one particular
way ; and secondly, because there is no such institute of
biology, or of geology, or of astronomy ; and, I take it,
that whatever ruling applies to the Fellowship of the
Chemical Society applies equally to that of the sister
societies. I concluae, therefore, that the Fellowship of
any scientific society confers, and should confer, to a
certain extent, a mark of qualification ; and if this be
denied, and it be contended that the Fellowship is quite
meaningless, I would ask what in the name of common
sense would be the logic of a man's writing F.C.S., or
F.L.S., or F.G.S., &c., after his name ? No perfedly sane
person would dream of writing himself as a Fellow of the
Society of Arts, or of the Numismatic Society, or of the
Royal Institution, simply because in all these cases it is
perfedly understood that there is no sort, kind, or con-
dition of qualification necessary for eleAion to the
'* Fellowship *' ; whereas it has always been understood
that no one without competent scientific knowledge can
obtain the Fellowship of the scientific societies.

In the next place I fully admit that the other societies
should make no attempt to arrogate to themselves the
fundions of the Royal ; the analogy and reference seem
to me unfortunate and misleading, since the fundions are
so very different. The fundion of the Royal Society is
to honour original research and this only, not to signalise
merely acquired learning ; whereas my contention is that
the Fellowship of the other societies should mark simply
competent knowledge — thorough studentship that is — and
most emphatically not in any way imply original work.
I think this distindion very important, since at the recent
meetings of the Chemical and the Linnean several
speakers were knocking their heads against this desired



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