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forming the coast for several miles near Mingan. Finally, it
is widdfy spread on the coast of Labrador, where its character-
istic mineral was first found, and from whence it takes its name.
* Geology of C&Qada, 1863, page 480.

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182 T. & Hunt on Narits EocL

Pro£ A. S. Packard, Jr., has given us valuable mfonnation
with regard to the occurreiKje of labradorite rocks at some

£>int8 on the Labrador ooast^ One of its localities is at Square
land, just north of Cape St Michel, where the rock consists
chiefly of crystalline labradorite smoky gray in color, trans-
lucent, and opalescent with greenish reflections. This feldspar
often shows cleavage planes two inches broad, and is associated
with a little vitreous quartz and with coarsely crystalline
hvpersthene, which appears in relief on the weathered surfaces.
This labradorite rock, according to Prof Packard, is sur-
rounded by and probably rests upon Laurentian gneis& At
Domino Harbor he found domes or bosses of a similar labrador-
ite resting upon strata which consist in great part of a slightly
schistose quartsdte, having for its base a granular vitreous quartz,
and enclosing grains of black hornblende, more rarely hypers-
thene, black mica, and red garnet Feldspar is generally want-
ing, but in some parts these quartzites oecome gneissic, and
they were nowhere seen in unoomformable contact with the
Laurentian gneiss of the vicinity. These quartzose strata Prof.
Packard refers, with some doubt, to the Huronian system. The
minerals which they contain are not however met with, so far
as known, in the Huronian quartzites, and on the contrary, are
very characteristic of the quartzites of the Laurentian system,
which attain a great thickness in many parts of its distribution.
The overlying aomes of labradorite roct, which Prof. Piickard
was inclined to r^ard, in this case, as erupted through Huronian
quartzites, are probablv nothing more than outlying portions of
the newer Labrador K>rmation resting upon the Laurentian
strata, as already observed by him at Square Island. Along
the western coast of/ the island of Newfoundland Mr. Jukes
observed at Lidian Head and at York Harbor dark colored
rocks composed of labradorite and hypersthene, and others of
albite (?) and hypersthene, which may probably be found to
belong to the Labrador seriea

Rocks composed chiefly of labradorite or a related feldspar
greatly predominate in the Labrador series, but these, at least
m the area near Montreal, which is the one best known, are
interstratified with beds of a kind of diabase in which dark
green pyroxene prevails, with crystalline limestone similar in
mineralogical characters to that of the Laurentian ^Btem, and
more rarely with quartzites and thin beds of orthoclase gneiss.
I have more than once insisted upon the rarity of f5ree quarts
and the ^neral basic character of the rocks in this series, an
observation with which I am credited in Dana's Manual of G^l-

* On the Glacial phenomena of Lahrador and Maine. Mem. Boat Acad. Nat:
Hist, Tol. 1, part ii, pp. 214-217.

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T. & Hunt on Norite Rock. 188

ogy (p. 189), where it seems to be applied to the whole of the
rocks there classed as Azoic, including the Laurentian, Labra-
dorian and Huronian system& It is, in fstct, remarkable that the
silicated rocks of the latter two consist chiefly of labradorites,
diorites and diabases ; gneissic and granitic rocks bein^ exceed-
ingly rare among them, though quartzites abound in the Huro-
nian. In the Laurentian system, on the contrary, though basic
silicated rocks are not wanting, orthoclase gneisses, often grani-
toid in structure^ and abounding in quartz, predominate.

The anorthosite rocks of the Labrador series present great
variations in texture, beinc sometimes coarsely granitoid, and
at other times finely granmar. They not unfrequently assume
the banded structure of gneiss, lines of pyroxene, hypersthene,
garnet, titanic iron ore or mica marking the planes of stratifi-
cation. Probably three-fourths of the anorthosites of this
series in Canada, whether examined in place or in the boulders
which abound in the St Lawrence valley, consist of pure or
nearly pure feldspar rocks, in which the proportion of foreign
miuCTals will not exceed five hundredths. Hence we have come
to designate them by the name of labradorite rock. The colors
of this rock are very generally some shade of blue, fix>m bluish-
black or violet to bluish-grav, snroky gray or lavender, more
rarely purplish passing into flesh red, greenish-blue, and occa-
sionally greenish or bluish-white. The weathered surfaces of
these labradorite rocks are opaque white. The anorthosites
which occupy a considerable area in the Adirondack region, as
described by Emmons in his report on the Geology of the
Northern district of New York, and as seen by me in hand
specimens, closely resemble the rocks of the Labrador series in

In all of these localities the coarse or granitoid varieties often
hold large crystalline cleavable masses, generally polysynthetic
macles, and n^uently exhibiting the peculiar opalescence which
belongs to labradorite. Although rocks composed of labrado-
rite or similar feldspars, with hornblende or pyroxene, occur in
various other geological formations, both as indigenous green-
stones and as erupted masses, they never, so far as my olServa-
tion in North America goes, exhibit the peculiar character just
described ; namely, that of a granular or granitoid rock com-
posed of nearly pure labradorite or some closely related
feldspar, firequently opalescent, and generally of a bluish color,
often violet, smoky blue or lavender blue. This type of rock
seems in North America to characterize the Labrador series.

It may here be remarked as an interesting fact bearing on
the distribution of the Labrador series, that two large boulders
of labradorite rock, one of the beautiful dark blue variety, are
found on Marblehead Neck on the coast of Massachusetta It

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184 T. & Hv/nt on Norite Bock

does not seem probable that these masses could have been
derived fix)m any of the far oflF localities already mentioned,
and the fact that the gneiss of eastern Massachnsetts is, as I
have recently found, in part of Laurentian age, suggests that
an outcrop of the Labrador series may exist in some locality
not &r removed. In this connection it may be added that I
have lately found characteristic labradorite and hyperite rocks
in southern New Brunswick, a few miles east of St John,
occupying a position between the Laurentian and the Huronian
or Cambrian rocks, which there make their appearance, accom-
panied by Lower Silurian strata, to the south of the great
Carboniferous basin of the r^on. This interesting loc^ity
was recently pointed out to me by Mr. G. P. Matthew oi St John,
to whom we are indebted for a great i)art of our knowledge of
the geology of southern New Brunswick. Chester and Bucks
counties in Pennsylvania, and the Wichita Mountains in Arkan-
sas, are cited in Dana's Mineralogy as localities of labradorite,
but as I have never examined specimens from these places, I
am unable to say whether they resemble the characteristic anor-
thosites of the Labrador series already described.

The name of norite, in allusion to Norway, was given by
Esmark to a rock composed chiefly of labradorite, which is
found in several localities in that country.* I had already
noticed the close resemblance between two specimens of norite
obtained from Ej^ntz of Berlin, and the labradorite rocks of
North America just noticed, when in 1867 1 had the opportunity
of examining at the Universal Exhibition at Paris, a collection
of Norwegian rocks selected for ornamental purposes, exhibited
by the Royal University of Christiania. Prominent among
these was a series of the norites, which could not be distin-
guished from the labradorite rocks of the Ui)per Laurentian or
Labrador series of this continent In a printed note accom-
panying this collection from the University it is said that the
numerous varieties of rocks consisting of labradorite with
hypersthene, diallage and bronzite, have, in the geological map
of Southern Norway, published at Christiania in 1866, been
designated by the common name of gabbra This note at the
same time suggests that " the name of norite should be i)re-
served for certain varieties of ^abbro rich in labradorite, which
varieties mav in great part with justice be called labradorite
rock, since labrador feldspar is their predominent element."
With this excellent suggestion I heartily concur, remarking,
however that the name of gabbro, as an ill-defined synonym
for certain anorthosite rocks, including in part diorite, diabase,
hyperite, and even confounded with the non-feldspathic rock
euphotide, may very well be dispensed with in lithology.

* See farther Zirkel Petr(]^raphie, n, 131.

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T. S. Hunt on NoriteBock. 185

By referring to the geological map just mentioned, it will be
seen that these so-called gabbros occupy considerable areas in
the Laurentian gneiss region of Norway. By the authors of
the maps, Messrs. Kjerulf and Dahl, these gabbros are regarded
as eruptive, though they are described at the same time as often
assummg the character of stratified rocks. It should however
be noticed that these geologists go so far as to regard the whole
of the granitic gneiss of the region as unstratified and of plu-
tonic origin.

The specimens of these norites exhibited in Paris were in
blocks polished on one side, and as was observed in the note
accompanying them, presented a curious resemblance to certain
varieties of marbla It is worthy of remark that Emmons in
his report on the Geology of the Northern District of New
York, suggested the application of the labradorite rocks of
Essex county as a substitute for marble (pages 29, 418). An
ornamental vase of the same rock turned in a lathe with the
aid of a black diamond, has been in the Museum of the Geo-
logical Survey of Canada since 1856.

Of the collection of norites from Norway the specimens from
Sogndal and Egersund presented fine varieties of grayish or
brownish violet tints, while a dark violet norite came from
Krageroe and also from the islands of Langoe and Gomoe, and
a white granular variety from the gulf of Laerdal in the diocese
of Bergen.

It is onlv in rare cases that the cleavable feldspar of these
norites exnibits the peculiar opalescence which distinguishes
the finer labradorite found in some parts of the coast of Labra-
dor. Opalescent varieties of this feldspar are however occa-
sionally met with in the area near to Montreal, and in northern
New York. In the Paris Exhibition of 1867 there were
exhibited from Eussia, large polished tables of a beautiful
violet colored granitoid nonte, portions of which exhibited a
fine opalescence. This rock, I was informed, comes from a
mountain mass in the Government of Kiew, but of its geognos-
tical relations I am ignorant

These peculiar labradorite rocks, presenting a great similarity
in mineralogical and lithological character, have now been
observed in Essex county, New York, and through Canada at
intervals from the shore of Lake Huron to the coast of Labra-
dor. They are again met with in southern New Brunswick,
in the Isle of Skye, in Norway, and in southwestern Bussia,
and in nearly all of these localities are known to occur in con-
tact with ana apparently reposing like a newer formation upon
the ancient Laurentian gneisa Giekie in his memoir on the
geology of a part of Skye,* appears to include the norites or
♦ Quar. Jour. G«oL Soa, xiy., p. 1.

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186 A. A. Hayes on ike Color of the Water of Lake Leman,

hypersthenites of that island with certain syenites and green-
stones, which he describes as not intrusive, tliough eruptive
after the manner of granites (loc. cit, p. 11-14). The hypers-
thenites are represented in his map as occurring to the west of
Loch Slapin. Specimens in my possession from Loch Scavig,
a little further west, and others in MacCulloch's collection fix)m
that vicinity, are however identical with the North American
norites, whose stratified character is undoubted. I called atten-
tion to these resemblances in the Dublin Quarterly Journal for
July, 1863,* and Haughton, who in 1864 visited Loch Scavig,
has since described and analyzed the rock of that locality,
which consists of labradorite^ often coarse grained, with pyrox-
ene and menaccanite, and is evidently, according to him, a bedded
metamorphic rock (Dublin Quar. Jour., 1865, p. 94^ He, it may
be remarked, designates it as a syenite, a term which most litho-
logists apply to rocks whose felaspar is orthoclase.

I desire to call the attention of both American and European
lithologists to this remarkable class of rocks, of which the
norites may be regarded as the normal and typical form, in the
hope that they may be induced to examine still fiirther into the
question of the age and geognostical relations of these rocks in
various regions, and to determine whether the mineralogical and
lithological character which I have pointed out are geological

Art. XXHL — On the cause of the color of the Waier of Lake
Lemauy Geneva; by Aug. A. Hayes, M.D., Assayer to State
of Massachusetts.

The traveler, who enters Switzerland at Geneva, always has
his attention arrested by the beautiful azure color which the
water of Lake Leman presents, especially when, as one looks
into its depths, the color ie in contrast with the white reflection
of clothing below the surfiace, at points where the laundresses
pursue their avocations,

* I, at the same time, called attention to the Laurentian aspect of the crjstalliDe
limeBtones of lona, which I found in MacCulloch's ooUection. Limestones not imlike
these occur in Skye, intermixed with serpentine, and are, according to Mr. Giekie,
associated with the protruded syenites of that region. With all deference to. the
authority of that eminent geologist, I cannot help suggesting that a reexamination
of the Strict would show thnt the highly-inclined metamorphic crystalline lime-
stones, holding serpentine, and associated with syenitic rocks, belong to an older
system (probably Laurentian), and are thus distinct from the nearly horizontid foe-
dhferous lia»sic limestones near by, which are only locally altered by mtrusive rocks.
American geologists will at ouoe recall the mis-conception which led most of our
best observers during many years to look upon the old Laurentian limestones of
New York and New Jersey as altered portions of the overlying paleozoic strata.

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A. A. Hayes on the Color of the Water of Lake Leman, 187 .

Many will remember the expression of Sir H. Davy, that
"this color is doubtless due to some compound of iodine,"
and not only chemists, but geologists have speculated on the
cause of this coloration, quite frequently with opposite opinions.

Both in composition and general characters, this water oelongs
to a class I have been accustomed to describe as "White
waters," or colorless waters, which, chemically considered, al-
ways hold a salt called crenate of lime in solution, and mark
in their color the existence of lime salts, in their course as rivers,
or in contact with them, as reposing in true lakes. At many
points in Switzerland these white waters are found, and indi-
cate clearly the occurrence of calcareous matter, more exten-
sively diffused than surface observations of the rocks would
allow in some districts.

Among the Tyrolese Alps, too, lakes and streams present the
same cerulean hue, which gives character and beauty to the
water of Lake Lenaan, and I have seen even small collections
of water there apparently as highly colored as the more noted
lakes. "Whitewaters, when dear, always present this hue,
and when turbid, a green hue, due to reflection from particles
of solid matter. In the summer of 1858, I commencea a care-
ful analysis of the water of Lake Leman at Geneva, and had
found a general accordance with the published statements of
composition ; but the special search for coloring matter, was
prevented by the inopportune recurrence of rain, and subse-
quent disappointment at a point on the Ehone above the laka

Since that time this water has been analvzed by distinguished
chemists, such as Will, Dafour, and Blanche, whose results only
show the presence of more salts in number in the solid matter,
and the slight variations in proportions which we should expect
would occur, under variations of volume and temperature, in
the water at different seasons.

These analyses, I learned, were made in the usual way of
evaporating the water for the solid products, and driving off and
collecting tne gases, a method which enables us to answer many
questions, but does not permit the nicer determinations of or-
ganic bodies, if present, in a natural or an altered state. Anal-
ysis so conducted would not allow us to answer the question
m relation to the cause of color, unless it could be traced to
some known or unknown fixed compound. Nor would such
an analysis determine the weight accurately of the whole amount
of matter, naturally dissolved in the water, as it is easy to prove
that a loss of matter takes place during the evaporation, even if
conducted at a moderate temperature — ^the great point of state
of hydration of the organic salts, and to some extent that of the
saline matter, is ignored entirelv when we proceed in this way
to determine the quantity and kind of constituents.

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188 A. A. Hayes on ike Color of the Water of Lake Leman.

Nearly all waters contain living organisms, and their germs,
these matters, in a decomposing state, organic acids, either with
or without bases, in the form of salts, most easily changed by
heat or even by concentration. These substances are very im-
portant constituents, in connection with the uses of the water,
and I could offer many illustrations of damage in manufectur-
ing and unfitness for consumption, traceable directly to the pres-
ence of such bodies in waters otherwise desirable, and proper for
extended consumption.

The mode adopted in my examination of the water of Lake
Leman is that which I have usefully applied in a large number
of cases, and with modifications, it is applicable to all waters, in
connection with other well known steps of analysis.

A large volume of the water of Lake Leman was mixed with
a small portion of a diluted solution of sub-acetate of lead
quickly and uniformly diffused. Another portion was treated
in the same way, with a water solution of pure soap — ^both pre-
cipitates slowly formed, were collected in a moist state, sub-
sequently examined by the microscope, and were found to con- .
tain only the ordinary constituents of white waters, when so

The negative results of these trials in this connection, were
sufficient to prove the absence of all coloring or colored bodies
in this water — ^the strong attraction of the basic salt of lead for
all coloring matter is well known — ^its power of removing col-
ored infusoria is equally great The calcareous soap product
formed fix)m the test removes all suspended matter, and permits
us to detect organic forms with ease and certainty, after the fat-
ty matters are dissolved on a glass slide.

It is obvious that in cases of complete analysis of waters,
these precipitates should be subsequently chemically treated,
and their state of hydration found, and engaged compounds sep-
arated and weighed

Chemical analysis, thus conducted, having thrown no light on
the cause of color in this water, has proved the absence of col-
oring substances, and placed it in the list of those waters, which
do not exhibit the color seen in this lake ; we are, therefore, led
to ascribe the origin of its peculiar tint to natural influences,
namely, the reflection and refi-action of an azure sky in a color-
less water.

The sky coloration of this part of Switzerland early engaged
the observation of Saussure, who even experimented on its depth
of color, while retaining its blue tint All the conditions favor-
ing almost constant blueness of sky, are present in this, and
other parts of Switzerland in a marked degree, and I believe
that extended observation will always connect the blue tint of
white water with the deep azure hue of the clear sky above it

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& p. Sadtler on Fischer's Salt 189

By carefiilly watching the influence of the light fix)ni the sky
on the water of this Idee, I observed here as elsewhere that
depth of color and tint in the water were modified greatly, or
even lost under varied light from the sky. As the sun declined
the azure tint was replaced by a grayish hue, or a light gray
color was the closing hue of a series of shades of color. If the
clear sky became flecked with small cloud surfeces, the water
responded in unequal coloration, as if the water mirrored the
sky, under this condition of beauty.

In other countries, there are bodies of colorless water which
do not exhibit the coloration, commonly seen in Lake Leman
water. Such localities are not fevored with clear blue skies
through atmospheric constitution, and bluish greenness of tint
is the nearest approach to azure hue, which the sky permits,
excepting perhaps at rare momenta

The n^ative results of chemical analysis, and the sufficiency
of the effect of reflected and refracted ught of the sky, which
is over the water of Lake Leman, led me to the conclusion that
the cause of color is found in the peculiar hue of the sky, so
transmitted to the eye by a colorless water.

Boston, Haas., Deoember lOdi, 1869.

Abt. XXrV. — (hntribviions to Chemistryjrom the Laboratory of
the Lawrence Scientific School. No. DL — On t/ie Potaasio-
Oobaltic Nitrite known as Fischer's Saltj and some analogous and
related compounds; by Samuel P. Sadtleb.

The composition of the double nitrite of cobalt and
potash, known by the different names of " Fischer's Salt " and
" Cobalt-yellow, has long been an open question. The follow-
ing is a brief statement of the views advanced on the subject
Fischer* the discoverer of the salt made no analyses of it St
Evre+ who rediscovered it gave as a formula for it KaON,04-f-
€oONt04, but does not give the analytical data. StromeyerJ
subsequently showed the incorrectness of this view and wrote
the formula €0,0^ 2N,es+8(K,eN,es)+2Hae. This formula
is peculiar in making tiie atom ^o^Os combine with 2 atoms of
NaO,. We shall discuss the formula and resxdts farther on.
Erdmaim§ first pointed out a distinction between the salt
formed in neutral solutions and the salt formed in acid solutions,
which latter he considers as a normal salt He gives both
2€oe, 8N,es-f-8(K,eNae8)-f-8Nae, and €oae,8Nae8+

* Fogg. Aim., Izxii, 477 and Izxir, 124. X Ann. Ch. u. Ph., xcvi, 218.

t Jr. pr. Gh., 64, 84 and 68, 186. g Jr. pr. Ch., Izziii, 698.

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190 & P, SadOer on Fischer's Salt

or as we shall write it €o86Nea+6(KNe8) fSHaO. Braxm* the
last writer on the subject, passes most of the preceding work in
review. He takes up Stromever's results, and rejecting hia
views as to the composition of the salt analysed by him, fiffures
for it a number of ingenious but somewhat complicated form-
ulas. He considers that neither the "neutral salt" nor the
** acid salt" of Erdmann can be regarded as anything but mix-
tures or " poly combinations," and for the first of them con-
sidered as such h e g ives a still more ingenious and com-
plicated formula. We quote it as reduced to its empirical
form by Blomstrand rf Cc)oB[8»Nii2H2q0464p$ Braun's own results
are expressed first by a formula containing both CJojOj and CoO,
then by one containing "GojO,, OoO, NgOj and N2O5 and finally
by the following :
8(€o2e8, 8Naes+4K3e,4Nae,+2Hae)+2(€o8e^H,e, 21^^+

KaO, NaOg+SHaO).
The experiments made to settle its composition and the results
obtained are as follows : St Evre ignitea the salt in a stream of
nitrogen. Nitric oxyd was given oflF and the residue was a
black oxyd, which on contact with HCl gave CI and with
O3H8O4 gave OO,. This I cannot regard as conclusive, as
mere igmtion per se will not break up the KNO,, so that the
residue was not pure "GojOj, ; moreover the NaOg in breaking up
may have given an atom of to form the €020,. Stromeyw
found that NaHO and BaHaOj decompose it on gentle warming,
even with exclusion of air, separatmg the brown hydrat^

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