Rodolfo Amedeo Lanciani.

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and widely accepted among American gas engineers to the
effect, that the weight of water heated firom the fireezing to the
boiling point by one cubic foot of the four main components of
illuminating gas, respectively, is as follows :

Hydrogen 2*22 lbs. water.

Carbonic oxyd 2*16 " "

Marshgas 6-17 " "

defiant gas 10*74 " «

The figures here being obviously about in the same ratio as
those in the second column of Table L Several most grave
errors, however, are here involved. To get at the true relative
calorific effects of the above gases, when burned in the open air,
in heating water below its boiling point, deductions must be
made, not only for the specific heats of the products of combus-
tion of the gas, but also, more important still, for the specific
heat of the nitrogen of the air required to bum the gas. In
feet, when we consider that for each volume of oxygen required
to bum a given volume of a gas, about four volumes of nitrogen
must be heated up to the temperatures of the flame, it becomes
easy to conceive, what is actually the fact, that within certain
limits the waste of heat due to this cause alone counterbalances
altogether the advantage that would be supposed to result fix)m
the crowding of combustible matter into so condensed a form
as in the illuminating hydrocarbons. The result of our investi-
gations of this matter is that the heating powers of the flames
of pure hydrogen and pure olefiant gas, even when used to the
greatest advantage, to neat water below its boiling point, are
almost or quite iaentical

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842 SiUiman and Wurtz an Flame TemjoeraMires.

In this discussion we have occasion to use the numbers repre-
senting the specific heats of but three gases, the three, namely,
which remain after c<Mnplete combustion, «foam, carbonic add and
nitrogen ; as we must assume that in the hottest and most lumi
nous zone or shell of the flame, there is no oxygen in excess to
be heated. These three numbers are, according to Renault's
latest determinations, for equal weights of

Steam 0*4806

Carbonic acid . 0*2168

Nitrogen 0*2438

{Liquid water being 1*0000)

This means that the amounts of heat which would raise one
pound of water and steam to the same degree are in the ratio of
04805 for the pound of steam, and 1 for the pound of water.

2. Calculation of the calorific effects of Hydrogen burning in axr,
— ^Let us take, firstj the simplest case possible, that of hydrogen
with exactly the right admixture of pure oxygen to Dum it,
which, by Table I, develops a total heat of 84462'' C. ; that is,
would heat a certain weight of liquid water to this temperature.
In order to find the actual amount of heat contained in the pro-
ducts of combustion, we must first take into account the fact
that one {>ound of hydrogen bums to nine pounds of steam, and
then obtain the ratio between the above number, 34462, and
the amount of heat necessary to heat nine times the weight of
steam ; that is, nine times the specific heat of steam. Calling
the total residual heat in the produced steam x, we have the
simple proportion :
9x(sp. heatofsteam=0-4805): 34462^ ::(sp. heatof water=l):a;

or, X = ^^ =7969^ C* = 14376° P. ;

a number which, we may add, represents the maximum of heat
capable of being imparted theoretically to liquid water by the
flaine of Harems oxyhydrogen blow-pipe.

Still, we have by no means here the actual temperature of
the firee or open flame of Hare's blow -pipe, which is generally
lower than this figure ; as we have not yet taken into account
the latent heat, or heat of vaporization, of the 9 lbs. of steam
formed. The Centigrade temperature necessary to convert 1 lb.

* Bunaen, in his Ghksometry (English edition of 1867, p. 242), giyes this number
as 8061° 0., the difference being due to his using a different number for the spe-
cific heat of steam, namely, 0*476, apparently an earlier determination of Regnault.
Bunsen makes here the singular oversight of regarding this flg^ure as the tempera-
ture, when <* the gases can fVeely expand, as is the case in an open flame," over-
looking the correction necessary in this case for the himt heai of steam ofcombua*
Akm, as is explained in the text above. This oversight has doubtless been corrected
by the distinguished author, but we have been unable to ascertain where the cor-
rection has been published.

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SiUiman and Wurtz on Flame Temperatures, 848

of water into steam being 537^ ; to get the actual temperature
of the oxyhydrogen flame, we must modify the above equation,
so that

^^84462M9x58n =e851» 0. = 12864° P. ;
4-8245 '

which is the temperature actually possible in the flame of the
compound blow-pipe, were the combustion instantaneous and

When hydrogen gas bums in air^ however, as has been
before statOT, another deduction of enormous amount must be
made from the above figures, due to the heat required to expand
the nitrogen. This is obtained simply by adding to the divisor,
as above, the weight of the nitrogen of the air employed, inul-
tiplied by its specific heat The weight of the nitrogen in air=
8'318 times the oxygen ; so that the latter of the aoove equa-
tions becomes

^ 34462-^(9x637<^) ^ ^^ o q ^^g^^o j
^4-32454-(8x8-318x 0-2488)^^^^ 0.-4^72 if.

"We have here a full explanation of the extraordinary loss of

Eower in illuminating gas by admixture of air, wnich we
ave discussed elsewhere.* The nitrogen of such air is not
merely a diluent, or even a mere deductive quantity ; its specific
heat is an actual divisory function in diminishing tne flame-tem-

This, then, is the actual temperature to which the flame of
hydrogen gas burning in the atmosphere might attain to, sup-
posing complete and mstantaneous combustion. If it is desired
to obtain instead, the total calorific effectiveness, as in heating
water below its boiling point — in which case the .latent heat of
the steam of combustion becomes also available — ^the above
expression is changed by simply omitting the subtrahend in
the numerator :

3. (hhulation of the calorific effect of carbonic oxyd burning in
air, — ^As the product of combustion is here solely carbonic acid,
no latent heat of steam enters, and the calorific eflfectiveness
is the same, imder all circumstances, in air. In the numerator
we substitute of course the calorific ec^uivalent of one volume
of carbonic oxyd from Table I ; and m the denominator, for
the specific heat of 9 lbs. of water, that of 22 lbs. of carbonic
acid, Doing the weight of the latter formed by the combustion
and combination of 14 lbs. of carbonic oxyd, with 8 lbs. of

* Tills Journal, n, zlyMi, 40.

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844 Silliman and Wurtz on Flame Temperatures,

oxygen. The number for the specific heat of nitix^en is the
same as before ; and the equation is now

4. Marsh gas and Olefiani gas. — In these two cases, we have as
products of combustion both carbonic acid and water; and,
therefore, when the calorific effects are sought for, we have
not only the latent heat of steam entering as a subtrahend
into the numerator ; but also into the denominator, as divisors,
all three of the specific heats of steam, carbonic acid, and nitro-

Then, as 8 lbs. of marsh gas consume 22 lbs. of oxygen, and
produce 22 Iba of carbonic acid, and 18 lbs. steam ; and as
14 lbs. of defiant gas consume 48 lbs. of oxygen, producing
44 lbs. of carbonic acid, and 18 Iba of steam, the equations for
the calorific powers of their flames in air become —

For marsh gas :

X = 104604O~(1 8X637O) ^ o C.=:4386° F.

(18X-4806) + (22X-2163) + (32X3-318X-2138)

And for olefiant gas :

X = . 166012O-(18X-637O) ^^743^ C.=4970^ F.


"When the deduction for the latent heat of the steam of com-
bustion is not made, the results in these two gases are consider-
ably higher, as will be obvious from mere inspection of the

We shall now give, in tabular form, all the results of our
calculations of the calorific powers when burning in the air, of
the four gases we have to deal with.

Table IL

For equal yolumes of the Calorific effects in heat- Cabriflc effects, above
gases burning in air. ing liquid water. 100^ G.

Centigrade Fahrenheit Centigrade Fahrenheit
degrees. degrees. degrees. degrees.

( (sp. heat HO=-4806) 31920 ) 6778°) 2744*> ) 4971*> )

Hydrogen ^(sp. heat HO=-4750) 32040 1 5799° V 2756® }. 4S9lo }■

((mean 3198<* ) 6788^ J 6749®) 4980®)

Oarbonicoxyd 29960 6426« 2»96« 6426°

Marsh gas, (^. heat HO=-4806). 2660o 4820° 2414° 4386°

Olefiant gas, " ** 2916° 6481° 2743° 4970<%

5. ComputaMon of calorific effects of mixed gases', — The above
table renders simple the calculation of the calorific effects of
any given gaseous mixture, whose centesimal composition is
known. It is only necessary to obtain the sum of the multiples

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SiUiman and Wurtz on Flame Temperatures. 845

of the percentage of each component ffas into its calorific capa-
city, as given in this table, and divide by 100.*

To serve as examples of these modes of computation we
here cite, in tabular forms, the results of some analyses of a
number ofgaseous mixtures, made by us during the winter of
1868-9. [These analytical results, it may be remarked, pos-
sess points of novelty and importance, both scientific and prac-
tical, which will bring them up again hereafter, in other connec-
tions. They are here placed on record.]

Table Hi, gives the results of two analyses of gaseous mix-
tures obtained by passing steam superheated to incandescence up-
ward through a mass of antlira/nte coal heated to a high degree
in a clay retort of a novel construction, according to what is
now known as the " Grwynne-Harris," or American Hydrocarbon
Qbs System. In this table the results are calculated without
carbonic acid and sulphuretted hydrogen, which, with traces of
nitrogen and sometimes of oxygen, are found in the unpurified
anthracite ga&

Table m.

No. 1. 1^0. 2. Mean.

Hydrogen 60-43 69-32 69-87

Carbonic oxyd 86-44 37-14 36-29

Marshgas 4-13 3-64 3-84

100-00 100-00 lpO-00

In Table IV, column 1 gives the results of the analysis of
the street gas served out at this period by the New Haven Gas
Light Company ; made fi-om Westmoreland coal enriched with
about six per cent of Albertite. Column 2, the mean of four
analyses of the completed hydrocarbon gas made by us at Fair
Haven during the same time, by combinmg gas from the same
Westmoreland coal (with 10 per cent of Albertite) with about
half its volume of the Anthracite gas. Columns 3 and 4 are
obtained from 1 and 2 by centesimal reduction, after deduction
of the illuminant ing^-edients, being what we propose to desig-
nate as the non-illuminating svbstrata of illuminatmg gases.

* Prof. Bunsen, in the masterly discussion of the subject presented in his GuS'
ometryf not having in yiew the exact object we propose, has used a train of reason-
ing and a mode of formulation of some complezitj, to follow which requires some
fit^e mathematical skill — ^part of his object having been to construct a formula so
general and comprehensive as to cover the direct computation, from any gaseous
mixture independently of its special calorific intensity. We have here aimed at so
ahnplifying as to bring the whole subject within the capacity of aU. Our above
tabulation of the individual gaseous components, as a starting point, seems to us to
accomplish this most effectually, so far as illuminating gases are concerned.

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846 SiUman and Wurtz on Flame Temperatwrea.

Table IV.

(I.) (2.) (S.) (4.)

HewHftTea FalrHftren Babttratnm

CttjOaB. Hydrooar- of New ofFatr

bon Qm. HftTen Om. H»TeB Qm.

Hydrogen 43-58 4677 4679 50-27

Carbonic oxyd... 214 9-66 2-31 10-27

Marsh gas 47-42 86-71 60-90 89-46

niuminants 6*86 6-96

10000 100-00 100-00 100-00

Table Y gives the results of the computation, fix)m our for-
mulae, of the calorific powers of these five gaseous mixtures, for
communicating temperatures both above and below that of aque-
ous ebullition. We should remark that we have here been
obliged to regard the volumes of illuminant hydrocarbons as rep-
resenting plefiant gas solely; both because we have no certam
data as to their retd nature, and particularly because, if we ac-
tually knew, or should assume, the nature of the hjrdrocarbon
vapors present, still we have no experimental calonfic equiva-
lents, as we have for olefiant gas, from which to start in such a
computation. We have reason to believe nevertheless that the
errors thus introduced are not important in amount

Table Y.

Welj[btoofwAfcer W*tB of water Ut column re- 8d column re*

eqoAlIjr taeftted equally heated dnoedtoN. dneedtoNew

below boil*ff ; bj Above Doa*g ; by HftTengM HaTengas

equal Yolunea. equal Tolnmea. —100. -'^

Anthracite gas 3100 2823 104-2 109*2

Substratum of the New Haven

street gas 291t 2681 98-1 996

Substratum of the Fair Haven

hydrocarbon gas 2962 2640 99*6 102*0

New Haven gas; with tiie U-

luminantsassumedasoleAant 2974 2692 100*0 100-0

Fair Haven gas ; with the 11-

luminants assumed=olefiant 2959 2647 99*6 102*1

8. Conclusions, — Some of the practical conclusions to which
we are led, by the results of the above investigations, are
somewtiat remarkable, so that we feel diffident recarding
them. It is however always safe to follow the leading of
truth, however astray she may conduct us fix)m our precon-
ceived notions.

From Table 11 it is apparent:

1. That of all known gases, the highest calorific effects, under
ordinary atmospheric conditions, are obtainable fix)m carbonic
oxyd; whose calorific value, above 100° C, is about 8000° C.

2. That, in absolute calorific value, below 100° C, in the at-
mospheric medium, hydrogen surpasses its volume of any other
gas; giving a temperature of about 8,200° C.

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H. Y. Hind on the Laurentiartj etc 847

3. That for all modes of application — ^that is, for producing
both high and low temperatures — ^the total maximum calorific
eflFectiveness of carbonic oxyd is a constant quantity.*

4. Compound condensed submultiple volumes of hydrogen,
Kke that in marsh gas, have much less total calorific value in air
than their volume of fi-ee hydrogen.

6. Condensed compound submultiple volumes of gaseous car-
bon, like that in olefiant gas, have no greater total calorific value,
in air below 100° C, than their own volume of carbon gas in
the form of carbonic oxyd ; while above lOO*' C. their value is
even considerably less.

Art. XXX VIL — On the Laurentian and Huronian Series in Nova
Scotia and New Brunswick; by Henby Youle Hind, M.A.

OONTEHis: — 1. Introduction; 2. General Sketch of the Distribution of the Huronian
and Laurentian Series in Nova Scotia ; 3. Sequence of Formations — The Upper
Silurian ; 4. The Lower Silurian ; 6. The Gold-bearing Rocks ; 6. The Cambrian
or Huronian Series; 7. The laurentian Series; 8. The Eozodn Canademe;
0. Cape Breton Island.

1. Introduction,

The descriptions contained in this paper, so^ far as they relate
to Nova Scotia, are in the main the results of observations
during the summers of 1868 and 1869, while making geological
surveys for the Nova Scotian government, in the gold districts of
Waverley and Sherbrooke. The comparisons with New Bruns-
wick are based on my official Eeport on the geology of that
Province ;+ and the references to Cfape Breton, when not other-
wise stated, are from MS. notes of explorations in that Island
during 1866.

The object of this paper is to show that two gneissoid series,
supposed to be the equivalents of the Huronian and Laurentian
of Sir W. E. Logan, are exposed over very large areas in Nova
Scotia, the Island of Cape Breton and in New jBrunswick. J

The boundaries of the series have been traced through parts
of Hali&x, Hituts and Guysborough counties in Nova Scotia.
In New Brunswick J numerous narrow belts extending from the

* Metallurffists, especiaUj, will appreciate the suggestive import of the truth,
presented under the first and third heads; here enunciated, as we think, for the
first time. It is to be noted that all the above effects belong to the mcmmum kinds
and, of course, reach their development onlj under the most favorable conditions
in each case respectively.

{Preliminary Report ontheOeology of New Brunswick: Fredericton, 1865.
In southern New Brunswick Prof. Bailej and Mr. Mathew have discovered
and described rocks of Laurentian and Huronian age. '* Observations on the
Oeologj of Southern New Brunswick : " Fredericton, 1866. Also see an able paper
bj Mr. Mathew in the Journal of the (Geological Society of Lcmdon for 1865.

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848 H. Y. Hind on the Laurentian and

bay of Chaleurs to the boundary line between New Brunswick
and Maine are supposed to represent the Laurentian and are
described in my Report on New Brunswick, published in 1865
^p. 42^2).

Geological maps of Nova Scotia were published by Dr.
Abraham Gesner in 1836,* by Dr. Dawson in 1865,t and in
1868,$ and by Sir William E. Logan in 1865§ and in 1869.|

Sir William Logan states, in the introduction to his Atlas of
Maps and Sections, that for the geology of Nova Scotia " a
manuscript map by Dr. J. W. Dawson, compiled from his own
resources, and those of Messrs. B. Brown and H. Poole, has
been the source of information. " Hence, in making the necessary
comparisons between the subject of this paper and the published
descriptions and maps of Nova Scotia, I shall have to refer
almost exclusively to Dr. Dawson's map of 1868, accompanying
the 2d edition of his beautiful work on Acadian Geology.

In a Preliminary Report^" on the supposed Laurentian of
Nova Scotia, I have quoted some passages from Dr. Dawson's
work, especially the explanation to the geological map, in which
the uncertainty of the Doundaries of formations, and the doubt-
ful age of some strata, is adverted to. The recognition of a
very large gneissoid area in Nova Scotia, supposed to represent
two series not hitherto described as occurring in the Province,
will enable some of the changes in part anticipated by Dr.
Dawson to be foreshadowed with some degree of accuracy ; and
it is proper to repeat here Dr. Dawson's first paragraph of the
" Explanations to the Geological Map " : — " The map in this
edition, though greatly improved, is still to be regarded as
merely a rude approximation to the truth, and the coloring in
many places, more especially in the interior, remote from the
coast lines, is little more than conjectural"

In various parts of "Acadian Geology " reference is made to
rocks which were suspected by Dr. Dawson to be older than the
Lower Silurian slates and quartzites. (See particularly page 620,
Acadian Geology, 2d edition). These will probably now be
classed with the Huronian series ; and the massive porphyroid
granitoid gneiss on which they rest, with the Laurentian.

Dr. Sterry Hunt visited Nova Scotia in November, 1867 " for
the purpose of making some observations on the gold-bearing

* Remarks on the Qeology and Mineralogy of NovaSootia: bj Abraham Gesner;
Halifax, 1836.

(Acadian Geology, Ist edition.
Acadian Greology, 2d edition ; Macmillan k Oo., London, 1868.
Atlas of Maps and Sections; Montreal, Dawson Brothers, 1866.
Geological Maps of Canada and the adjacent regions, 1869: London, Edward

^ Preliminary Report on a Gneissoid Series underlying the Gold-bearing Rodcs of
Nova Scotia, and supposed to be the equivalent of the Laurentian System ; Halifax,
N. S., Junuary 6, 1870.

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HuTonian Series in Nova Scoticb, 849

rocks of that Province, with the view of comparing them with
those of other parts of the dominion, and also of obtaining such
information as might be usefiil in the event of a geological
survey of Nova Scotia itself"

Dr. Hunt's stay in the Province was limited to four weeks in
the months of ISovember and December, and in the descriptions
which he has given in his official report to Sir W. E. Logan*
he quotes the following as the principal sources of information
about the geology and mineralogy of Nova Scotia : Dr.
Dawson's Acadian Geology, 1st ed. ; Mr. Poole's Report, 1862 ;
Mr. J. Campbell's Eeports, 1862 and 1863 ; Professor B. Sill-
man's Reports on Tangier, Waverley and Montague Gold
Fields, 1864.

Allusion is made in the Atlas of Maps and Sections of the
Greological Survey of Canada to the opinions expressed in my
Report on New Brunswick that mucn of the granites of that
Province consist of altered sedimentary strata. " Much of what
in Nova Scotia, New Brunswick and Maine, is represented on
the map as intrusive rock (chiefly granite) probably consists of
paleozoic strata altered in situ as a&eady suggestea by Dawson
and Hind. See the latter's Report on New Brunswick, 1865,
page 50." (Atlas of Maps and Sections, Geological Survey of
Canada, 1865, page 20).

The remarkable similarity which exists between the rocks
constitutijig part of the great gneissoid axis of New Brunswick
and the gneissoid series now described of Nova Scotia, coupled
with the equally marked similarity wiiich obtains between the
paleozoic strata resting on these gneisses in both Provinces (on
the Nipisiquit in N. B.), satisfies me that they are of the
same ^e.

2. General Sketch of the Distribution of the Huronian and Lauren-
tian Series in Nova Scotia.

In this general sketch of the old gneissic rocks of Nova
Scotia, thev are grouped together. In succeeding paragraphs it
is stated where tne BLuronian or Cambrian gneiss and scnist rest
on the old Laurentian meiss as &r as known.

The outcrop of the Laurentian and Huronian rocks in Hali-
fiix and Hants counties, N. S., has been traced j&om a point
seven miles west of Windsor on the Basin of Mines (Bay of
Fundy) to the Atlantic coast at Cape Sambro, a distance of
forty-eight miles in an air line, and sixty-four miles on the
margin of the outcrop. This is the northeasterly boimdary
of an immense area of the same rock series which fix)m informa-
tion hereafter noticed I believe continues with variable breadth

* Report of Dr. T. Sterrj Hunt, FJELa, on the Gold Begion of Noya Sootia ;
Ottawa, 1868.

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860 K Y. Hind on the Laurentian <md

to the Tusket Islands, near Yannouth, a distance of about one
hundred and thirty-five miles in an air lina

The area above described forms the western development of
the Laurentian and Huronian gneisses and schists in Nova Scotia
It is separated from the eastern development by a narrow but
profound valley occupied by Silurian strata, whose least breadth
IS eight milea The outcrop of the southwestern boundary of the
eastern development is not continuous, but embraces two areas
near Grand and Fletcher's Lakes, and an area of unknown but very
considerable and of variable width, stretching from Parker's Lake,
with some narrow interruption of Silurian strata which have
escaped denudation, probaoly all the way to the Strait of Canso
and Chedabucto Bay, a distance of one hundred and twenty
miles in an air line : so that, generally speaking, a Laurentian
axis, capped here and there by strata of Huronian ace, occupies
Nova Scotia, certainly in one place at least forty-eight miles in

The existence in Nova Scotia of all formations from the Trias
to the Laurentian, with the exception of the Permian,* may
now be considered as established. Whether the rocks noticed
in the foot-note are of Permian or Triassic age I am not able to
say, but judging from the descriptions given of the relations of
the Triassic to the Carboniferous by Dr. JJawson, I have hitherto
considered small unconformable patches in Cape Breton as of
Triassic age, and regarded them as the continuation of the
Prince Edward ]^land series, resting on Lower Carboniferous

The entire series from the Lower Carboniferous downward,
with the exception of the Devonian, is passed over in a journey
by rail from W indsor to Halifiuc, in a distance of fourteen miles.
Tjie Devonian occurs at Nictau, and rest there on Upper Silurian
slatesf which probably sweep round the Falmoutn mountains
and connect with the Upper Silurian near Windsor.

8. Sequence of Formatione — The Upper Silurian.
On the St Croix river, eight miles from Windsor, the Lower
Carboniferous grits are seen to rest on Upper Silurian argillites.

* In Cape Breton, at Jumping Brook, seven mOes northeast of Ghetican Island
on the Gulf coast, and at Trout Brook, five miles northeast above CSieticao, mottfed

Online LibraryRodolfo Amedeo LancianiThe American journal of science and arts → online text (page 40 of 109)