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MEMOIRS AND PROCEEDINGS
OF
THE MANCHESTER
LITERARY & PHILOSOPHICAL SOCIETY.
206.1 2
MeA-6
MEMOIRS AND PROCEEDINGS
/
?
OF
Pre WAN C EE SD EK
mee RARY & PHILOSOPHICAL
SOC He ry
FOURTH SERIES
DiC rer oH VOL UMA
MANCHESTER
36"GEORGE, STREET
1894
NOTE.
The authors of the several papers contained in this volume are
themselves accountable for all the statements and reasonings
which they have offered. In these particulars the Society must
not be considered as in any way responsible.
CONTENTS:
MEMOIRS. PAGE
Experiments on the Relation between Uniform Stress and Permanent
Strain in Wrought-iron and Steel. By T. E. Sranton, B.Sc.,
Demonstrator in the Whitworth Engineering Laboratory, Owens
College, Manchester. Communicated by Professor OSBORNE
REYNOLDS, F.R.S.
Some Aspects of Town Air as contrasted with that of the Country. By
Geo. Barry, D.Sc., Ph.D. eA ae Bats ce
On a New Sporiferous Spike from the Lancashire Coal Measures. By
THoMAs Hick, B.A., B.Sc., Assistant Lecturer in Botany, Owens
College, Manchester, and JAMES LoMax
Preliminary Experiments on the Latent Heat of Steam at 100°C. By
P. J Harroec, B.Sc. (Lond. and Vict.), Assistant Lecturer and late
Berkeley Fellow in the Owens College, and J. A. HARKER, D.Sc.
(Tiibingen), Berkeley Fellow in the Owens College. Communicated
by Professor ARTHUR SCHUSTER, Ph.D., F.R.S.
General, Morphological, and Histological Index to the Author’s Collective
Memoirs on the Fossil Plants of the Coal Measures. Part III. By
WILLIAM CRAWFORD WILLIAMSON, LL.D., F.R.S., &c., Foreign
Member of the Royal Swedish Academy ; Corresponding Member of
the Royal Society of Gottingen
Notes on Wudfenia Carinthiaca, Jacquin. By;JAMES'CosMO MELVILL,
MOA., F.L.S.
On the K-partitions of the R-gon. By the Rev. THos. P. KirKMAn,
Mex, E.R.S.
On the Osmotic Pressure of Solutions of Finite Concentration. By
Tuomas Ewan, B.Sc., Ph.D....
On the Treatment of Sewage with Basic Per-Salts of Iron under varying
conditions. By Harry GRIMSHAW, F.C.S. ...
An Analysis of the Electro-Motive Force and Current Curves of a Wilde
Alternator, under various conditions. By JuLIus FRITH, Hegin-
bottom Physical Scholar of the Owens College. Communicated by
ARTHUR SCHUSTER, Ph.D., F.R.S.
II
22
Sy
54
75
. 109
S 1St
V1. CONTENTS.
PAGE
On the Primary Structure of the Stem of Calamites. By THomas Hick,
B.A., B.Sc., Assistant Lecturer in Botany, Owens College. Com-
municated by F. E. Wertss, B.Sc., Professor of Botany in the Owens
College
On the Instantaneous Pressures produced in the Explosion-Wave. By H.
B. Drxon, F.R.S., Professor of Chemistry, and J. C. Cain, Eiger
1851 Exhibition Scholar in the Owens College
On the Influence of the Configuration and Direction of Coast Lines upon
the Rate and Range of the Secular Magnetic Declination. By HENRY
WILDE, F.R.S.
A Sketch of the History of the Canal and River Navigations of England
and Wales, and of their present condition, with suggestions for their
future development. By LIONEL B. WELLS, M.Inst.C.E. Com-
municated by RUPERT SWINDELLs, M.I.C.E.
PROCEEDINGS.
BaAILey, CHARLES, F.L.S.—On Gulls at Old Trafford...
On a Map of Palestine ... a ee ae
On the rapid advances in Keene of Fossil Botany
BAILEY, G. H., D.Sc., Ph.D.—On some aspects of Town Air as
contrasted with that of the Country
BoTToMLEY, JAMES, D.Sc., B.A., Ph.D.—On the Completion of
the Manchester Ship Canal...
Cuay, Dr. CHARLES.—Presentation of Bust of ...
Dixon, Pror. H. B., M.A., F.R.S.—On M. Moissan’s Isolation of
Fluorine
FARADAY, F. J., F.L.S., F.S.S.—On a deposit of dirt during foggy
weather on Spinning Cops of Yarn in a Mill ...
On the Canal Map by Mr. Swindells and Mr. Wells
GRIMSHAW, Harry, F.C.S.—On the Treatment of Sewage with Basic
Persulphate of Iron under varying conditions
GwyTHErR, R. F., M.A.—On an Aurora seen at Buttermere ...
Hartoec, P. J., B-Sc.—On the Latent Heat of Steam ..
9) 9)
HODGKINSON, ALEXANDER, M.B., B.Sc.—On the Fertilization of an
Orchid by Insect Agency
Hoyt, W.E., M.A.—On Shells recently acquired by the Manchester
Museum
On the Luminous Organs of Cuttle Fish
. 158
174
. 108
- I0O0
, OG
CONTENTS. Vil.
: PAGE
Hypr, Hrenry.—On the Growth of Maize near Manchester 19
Jones, Francis, F.R.S.Ed.—On Specimens of Marble exposed to
town air 30
Lamps, Horace, M.A., F.R.S.—On the mode of Propagation of Waves
through Water by a Moving Object 34
Lancpon, M. J., Ph.D.—On Specimens of the Salt of Technical
Chlorophyll 20
Lets, C. H.—On the determination of the Thermal Conductivity of
Winter ... 34
MELVILL, J. Cosmo, M.A., F.L.8.—On Bulimus labeo and various New
Zealand Insects 83
NICHOLSON FRANCIS, F.Z.S.—On Gulls at Old Trafford .. 86
REYNOLDS, OsBoRNE, LL.D., M.A., F.R.S., M.I.C.E.—On the Latent
Heat of Steam 31
On Kitchen Boiler Explosions 90
On an Aurora seen at Fallowfield . 107
SMITHELLS, Prof.—On Flame and Flame Spectra ... 98
SCHUSTER, ARTHUR, Ph.D., F.R.S., F.R.A.S.—On an Oak Tree struck
by Lightning .. QI
On Apparatus for testing Clinical Thermometers . 100
WEIss, Prof. F. E.—On Second Crops of Fruit on Raspberry Cee on
Second Flowers on Apple Trees, and on a Monstrous Wallflower... 20
On Pieces of Wood found in Gravel Beds near Stockport 35
WELLS, LIONEL B., M.I.C.E.—On the Inland Waterways of England
and Wales 32
WILDE, Henry, F.R.S.—On the Philosophical Uses to which the Cor-
poration Supply of Electricity may be put 93
General Meetings otk Ree ue ox me 305290, 96, 105
Annual General Meeting ee LT
Report of the Council with Obituary Notices of Archibald Sandeman,
John Tyndall, Heinrich Hertz, Arthur Milnes Marshall,
Charles Clay, and Thomas Armstrong 205
Treasurer’s Accounts 220
Meetings of the Natural History and Microscopical Section: Annual 173
Ordinary’ .,. ue re er Be a 10.20, 63,92, 99, 106
Annual Report of the Microscopical and Natural History Section— 2273,
List of the Council and Members 226
Vill. CONTENTS.
PLATES, -&c.
TO FACE PAGE
I.—To illustrate Mr. Melvill’s paper on Walfenia Carinthiaca van) 2
II.—To illustrate Mr. Kirkman’s paper on the K-partitions of the R-gon 109
III, IV, V, VI, VII, VIII.—To illustrate Mr. Frith’s paper on the Wilde
Alternator ... xe sais sit - ue ls yi sia: Ge
IX.—To illustrate Mr. Hick’s paper on the Stem of Calamites ... nen”, IO
X.—To illustrate Mr. Wilde’s paper on the influence of Coast-lines on
Magnetic Declination... ey vee a vas sii + G0
XI.—To illustrate Mr. Wells’s paper on Canal and River Navigation ... 204
CORRECTIONS.
On p. 40, line 11, the equation should be as follows :—
a
w | cdt im
a t
L W fea
tf
Page 98. Mr. Rospert Monp’s election recorded in ordinary
Meeting, took place at a duly summoned General Meeting on
the same evening.
MEMOIRS AND PROCEEDINGS
OF
meee MANCHESTER LITERARY AND
PmCOSOPEMICAL SOCIETY,
=
Ordinary Meeting, October 3rd, 1893.
Professor OSBORNE REYNOLDS, M.A., LL.D., F.R.S.,
Vice-President, in the Chair.
The thanks of the members were voted to the donors
of the books upon the table.
Mate STANTON, B.Sc, read a paper on “ Experi-
ments on the relation between Permanent Strain and Uni-
form Stress in Wrought Irons.”
Dr. G. H. BAILEY read a paper entitled “ Some Aspects
of Town Air as contrasted with that of the Country,” in
which he dwelt on the importance of quantitative investi-
gations as to the impurities other than carbonic acid present
in air as a measure of pollution, and urged that, however
minutethe quantities may be,they are sufficientto bringabout
serious disorganization in plant lifeand in human beings. In
illustration Dr. Bailey presented tables showing considerable
variations in the quantity of sulphur compounds present in
different localities in Manchester and London on clear days
and on slightly or densely foggy days. Some surprise was
caused by a table showing that during the dense fogs of
December last in Manchester and London there was a much
larger proportion of sulphur compounds present in the
London than in the Manchester air, notwithstanding the fact
that the coal consumed in Manchester is generally understood
to be much more sulphurous than that burnt in London.
Professor WEISS confirmed the statement made by Dr.
BAILEY.
2 Mr. T. E. STANTON ox
Experiments on the Relation between Uniform Stress
and Permanent Strain in Wrought-iron and Steel.
By T. E. Stanton, B.Sc., Demonstrator in the Whit-
worth Engineering Laboratory, Owens College,
Manchester. Communicated by Professor Osborne
Reynolds, F.R.S.
(Received October 21st, 1893.)
When an iron bar is subjected to uniform longitudinal
stress exceeding its elastic limit, the connection between
the stress and the permanent set of the material is
usually shown by means of a Stress-Strain diagram, in
which the stresses are represented by the ordinates, and the
corresponding elongations by the abscissae of the curve.
' These can be traced by an autographic apparatus attached
to the machine, several types of which are in use.
The objection to this method is, that the position of the
curve, and also its form, are greatly influenced by the rate
at which the load on the bar is increased. Prof. Ewing* has
also shown that the effect of a pause in the loading has a
hardening effect on the bar, which increases with the length
of the time during which the load is. kept constant. On
increasing the load after this interval, it is found that
permanent set does not again take place until a considerable
increase in the load has been made. This has been called
the “hardening effect of the time.”
An illustration of this is shown in zg, z, which is the
Stress-Strain diagram for a wrought-iron bar tested in the
following manner :—
The bar was turned accurately parallel and fixed in the
Testing Machine and a stress of 16 tons per square inch of
Ency. Britt., *‘ Strength of Materials,” 30-33.
a oa ee
‘NOILOAS IVILIN] 40 HON] AXYWNOS UGA SNOJ, NI ssaWLS
Uniform Stress and Permanent Strazn. 3
Fre. 8
STRESS-STRAIN DIAGRAM.
form of diagram for constant
ratio of loading from zero.
Diagram for bar subject to
initial stress of 16 tons with
increase of load every 20
minutes.
eases agram for bar subject to
initial stress of 16 tons kept
constant for 18 hours.
2 (Sea See SecA en CR Diagram for bar subject to
initial stress of 16°7 tons
kept constant for 46 hours.
PERMANENT SET IN A LENGTH OF I0 INCHES.
4 MR. TE STANTON 707
initial section applied, and kept constant for 20 minutes.
The extension of the bar practically ceased after 15 minutes.
On increasing the load it was found that no further per-
manent set took place until the stress had reached 17°0 tons
per square inch, at which point the bar commenced to draw
out rapidly. At 17°40 tons another pause of 20 minutes was
made, and the test continued as before. It is seen that the
hardening effect of each load extends through practically
the same range of stress.
In the same figure the dotted curve is the diagram for
a bar of the same length and sectional area as the first, but
loaded in a different manner. The same initial stress of
16 tons per square inch was applied, producing the same
permanent strain as before. The load was then kept
constant for 18 hours. On increasing the load no permanent
set took place until the stress had reached 18°8 tons per
square inch. After this the drawing out took place rapidly.
In this case, the hardening effect extended through an
increase of stress of 2°5 tons. A similar test was made on
a bar of the same material, the initial stress of 16°7 tons
being kept constant for 46 hours. In this case the hardening
effect extended through an increase of stress of 3°0 tons.
It is seen from the diagrams that when permanent set
again takes place, after the load being kept constant, that
the amount of extension depends on the time during which
the preceding stress has been kept constant.
Thus, in the tests of bars A and C, which were of the
same material and initial dimensions, the extension of A
for a stress of 20 tons was 1°125” ina length of 10”. The
extension of C for the same stress, after having been subject
to a stress of 16°7 tons for 46 hours was °762”, or 327 less
than that of A.
In order to establish a relation betweeen the stress and
permanent strain by experiment it was necessary that the
elongation caused by any given stress should not be affected
Uniform Stress and Permanent Strain. 5
by the time duration of previous stress. For this purpose a
bar of wrought-iron of very soft quality was cut up into nine
lengths of 20 inches, and the 20” bars turned parallel.
Each bar was placed in the testing machine and a given
stress applied, the full stress being attained in about one
minute. The load was kept constant for thirty minutes,
when the permanent strain was observed and the bar taken
out of the machine. The results of these experiments when
combined show that the relation between the stress and
permanent strain is given by the formula
p=Ce, |
where g=stress in tons per square inch on the reduced
section of the bar.
ua)
d
é€= permanent strain =
where /= initial length, 7’=stretched length, C = constant.
(iis relation is clearly seen im zg: 2, in which
Professor Reynolds’* method of logarithmic plotting is
used. Thus, if points whose ordinates and abscissae are
respectively the logarithms of ~ and e are plotted; these
points are found to lie on a straight line, the inclination of
which will give the value of £, which in the above experi-
ments was found to be ‘25.
Assuming the above formula, then in the case of the
nine bars, the maximum variation in the value of the con-
stant C is from 39°25 to 39°49, or o'6%.
It seemed probable that the permanent strains produced
_in testing a single bar by successive loads would not be
given by the above formula ; but in /zg. 2, where the results
for bars No. 2 and 7 are plotted, it is seen that the same
relation holds approximately for cases where the time
duration of the stress does not exceed 30 minutes.
In the case of bar No. 13, where the second stress
Phil. Trans. Roy. Soc., 1879—p. 753.
Mr. T. E. STANTON on
i i
Fic:
‘NIVYLS LNANVWYAd SO SWHLIYVSO1
‘NIVULG GNV SSHULS JO SHAUN OINHLIUVIOT
LOGARITHMS OF STRESSES.
Uniform Stress and Permanent Strain. 7
applied was kept constant for 66 hours, the hardening has a
marked effect on the next permanent sets, which were each
20% less than that due to the loads.
The above tests were all made on the same brand of
B.B.B. iron, the only variation being in the value of the
constant C. which, for bar No. 2, was 40°30, and for bar No.
gavas. 40°35.
Experiments were also made on some bars of mild
steel, the results for which are shown in fzg. 2. In these,
with a time duration of stress not exceeding 30 minutes, the
value of £ was found to be }. The results are also plotted
for the case of a mild steel bar,in which the initial stress was
kept constant for 18 hours.
Similar experiments made on nine specimens, cut from
a long bar of Crown BB iron, did not give such consistent
results. This was probably due to the varying hardness of
the material in different portions of the bar.
In the case of bars R1 and Rg taken from these, and
tested with successive loads at intervals of 20 and I5
minutes respectively, the value of £ was found to be ‘275
for Ri, and ‘265 for Rg. The combined results for the
other seven bars, each tested with one load only, gave ‘265
as the value of &.
Several other experiments were made on iron of different
qualities, including some on Low Moor iron. The results
showed that in the case of iron of a soft and fibrous nature,
the same law of permanent set held, but when the iron was
harder and showed a crystalline fracture the relation could
not be expressed in the above form.
If p,=stress on initial section of bar, then, assuming
the density to remain constant and taking the formula
p=Ce" (1)
we have
(2)
8 Mr. T. E. STANTON oz
the condition for a maximum value of #, being when
e=4.
Substituting this value for e in equation (2) we have,
taking C = 39'4,
Po= 22°45 tons per square inch.
This corresponds very closely with the mean maximum
stress of wrought-iron of this brand, experiments on rough
bars giving values of g, ranging from 21°8 to 20°70 tons.
TABLE “1.
Tests of nine specimens cut from a bar of wrought-iron. Brand
R.f., Crown BBB.
No. of Initial Final Permanent Stress on Value
Specm. Area. Area. Strain. Reduced Section. of C.
sq. in. sq. in. Tons.
Dis "7643 "7420 "03071 16°480 39°37
Line "7590 "7238 105,227 18°373 39°48
Z. 3 "7528 =. “6999 «08133, ; 20°077 ~~ )3Gme
Z. 4 ‘FOASS) as 7e 03978 17°620 =. 39°46
Z. 5 "7905 "7158" 06585 | 10073) aaa
Z,. 6 "7810 "7638 "02330 15°338 20°27
(LS "7600 FAL 702689 15893 39°25
ZO 7510 ries fe) 04668 18°306 39°38
Z. 9 ‘7560 - "7306 03490 «= 17068 = gaa
Test of one specimen cut from a bar of wrought-iron. Brand
R.H. Crown B.B.B. Duration of stress 15 minutes.
No. of Initial Final Permanent Stress on Value
Specm. Area. Area. Strain. Reduced Section. of C.
sq. in. sq. in. Tons.
Ze ‘7410 — —_— — —
— —— a 2ae "02450 15888 40°17
a — ap ROBIN, 03547 17°45 = 40°20
— — *7066 "05005 19°06 40°40
— — "6940 (O7 150 20°893 40°40
a — “‘O725 "10875 23°050 40°15
ee ee
> al a
Uniform Stress and Permanent Stratn. 9
Test of one specimen cut from a bar of wrought-iron. Brand
R.H, Crown B.B.B. Duration of stress 30 minutes.
No. of Initial Final Permanent Stress on Value
Specm. Area. Area. Strain. Reduced Section. Oi (Cs
sq. in. sq. in. Tons.
fa 7775 =e a i ris
nas oe "7646 *OL7 3a 14°583 40°20
Br — "7594 "02462 <« 16°000 40°39
ae ... %16"4
Ao — sp < SC ind Deo we
eve 2 eet fe . Se She a ee a
nee trom the floor. ye! se.) fe.) 16'6
Thus, as a matter of fact, so enormous is the amount of
sulphur in Manchester gas (it is usually at least double that
allowed by the Metropolitan Act as a maximum) that the
air of our rooms is liable to be as highly charged with
sulphurous acid as the street air is in a moderately bad fog.
It is probably only the relative dryness of the air which
prevents it from becoming absolutely unbearable.
Thus far, then, in the face of the numbers given, I
contend that my remarks amount to a demonstration that, as
a means of discriminating between polluted and unpolluted
air, and as a means of forming some estimate of the extent
of pollution, the determination of the sulphurous compounds
and of organic matter are much to be preferred to that
usually adopted, viz., an estimation of the carbonic acid.
I may add that an equally convenient and, perhaps, even
more valuable means lies in the direction of the estimation
of the micro-organisms. Miquel, in Paris, has done much in
this direction, but, though the difference between town and
country air is very great, systematic experiments carried
out at a sufficient number of stations in a town area have
yet to be made before any general conclusions can be drawn.
But any plea for such a method of examination of air
should have greater weight if it can be shown that the
matters which it is proposed to determine are themselves
injurious to life and health. Unfortunately the amount of
16 Dr. G. H. BAILEY ox
reliable information that we have is small; it is, however,
increasing rapidly.
Aitken (Proc. Roy. Soc. Edin. XX. 76) gives results which
go far to show that the ferszstence of town fogs (and it is
the persistence which lends them their virulence) is due to
the presence of sulphur compounds and mineral matters;
and Frankland years ago suggested that the condensible
hydrocarbons in air possess a similar property.
Oliver, in a report presented to the Royal Horticultural
Society this year (“Effects of Urban Fog upon Cultivated
Plants”), has shown that the presence of as little as 20 parts
per million of sulphurous acid will, zf the laght 2s also cut off
to the extent to which in towns zt zs cut off, bring about
injuries to plants comparable to those which actually occur
during fog. Also that mere traces of some hydrocarbons
and of pyridine, impurities both found in polluted air and
the deposits therefrom, are most injurious.
Then with regard to human beings, hardly a winter
passes without the death-rate from respiratory diseases at
times running up to three or four fold the normal. That
this is due, in some measure at least, to the abnormal pollu-
tion of the air, such as has been indicated, is highly probable.
It is a character practically confined to large towns; it is
specially characteristic of densely populated districts where
pollution of the air is most marked. Doubtless the preva-
lence of such ailments is largely affected by climatic
conditions, and their seriousness aggravated by a lowering
of tone of bodily health already established.
But this only raises the further question as to how
far this very lowering of tone is the result of the
constant inhaling of these minimal quantities of sulphur
compounds, organic matter, and the like. Even though
we are not yet in possession of sufficient information
to enable us to speak decisively, there can be little
room for doubt that the determination of these minor
ve a ee eee
ee = SS eee
Some Aspects of Town Air. age
constituents of town air and their further examination is
worthy of more attention than has hitherto been given to it.
And considering the importance of pure air, it would be
well if such analyses of air were frequently and systemati-
cally carried out by sanitary boards as a matter of routine
under some such scheme as the following :—
Azur of dwellings in special cases ;
The estimation of carbonic acid gas, of organic matter
and micro-organisms.
Aur of streets ;
The estimation of sulphur compounds, of suspended
organic matter, micro-organisms, and noxious gases.
18 PROCEEDINGS.
Ordinary Meeting, October 17th, 1893.
ro fessor ARTHUR SCHUSTER, Ph.D., F.R.S...2eee
President, in the Chair.
The thanks of the members were voted to the donors of
the books upon the table. ,
Reference was made to the deaths, since the close of the
previous session, of two of the Society’s members—Dr.
CHARLES CLAY, elected in 1841, and Mr. ARCHIBALD
SANDEMAN, M.A., formerly Professor of Mathematics in
Owens College, elected in 1851.
A bust of Dr. CLAY, executed in 1834, and presented to
the Society by his executors in accordance with his wish,
was exhibited.
Mr. FARADAY alluded to a peculiar deposit of dirt
during foggy weather on the spinning cops of yarn in a
mill. According to his informant, the deposit increased
when the gas was lighted, and so convinced were the firm
in question of this that they were proposing to fit up the
mill with the electric light on this account alone. A dis-
cussion ensued in which Mr. N. BRADLEY, Mr. C. BAILEY,
Mr. JOHN BoypD, Mr. ANGELL, Professor DIXON, and the
PRESIDENT took part. It was variously suggested that the
phenomenon might be due to the heat causing atmospheric
currents, and thus bringing more of the polluted air into
contact with the cops; to the fog preventing the escape of
the products of combustion into the outer air; to the
vaporisation of minute globules of water floating in the
atmosphere, solid matter held by them being thus permitted
to descend ; to the greater density of the fog, when it
became necessary to light the gas; and finally to the
lighting of the gas merely making the collection of dirt on -
PROCEEDINGS. 19
the cops visible, and thus giving rise to the illusion that it
was due to the lighting of the gas.
Etoressor Hi. 6. DIXON, F.R.S:., gave an account of
M. MOIssAN’s isolation of fluorine, as experimentally
illustrated at the meeting of the British Association at
Nottingham.
The Rev. THOMAS P. KIRKMAN, M.A., F.R.S., read a
paper on the “ K-partitions of the R-gon.”
[Microscopical and Natural History Sectzon.|
Ordinary Meeting, October goth, 1893.
Mr. PETER CAMERON, F.E.S., in the Chair.
Mr. HYDE referred to the past summer as having been
highly favourable to the growth of maize in this country,
and specially mentioned that grown in Alexandra Park,
specimens of which were seven and eight feet in height with
cobs in an almost ripe condition. Other plants noticed
esrowing in the park were:—the castor oil plant, the tobacco
plant, the mallow, the eucalyptus.
20 PROCEEDINGS.
Ordinary Meeting, October 31st, 1893.
Professor ARTHUR SCHUSTER, Ph.D., F.R.S., F.R, Ales
President, in the Chair.
The thanks of the members were voted to the donors
of the books upon the table.
Mr. FARADAY exhibited some specimens of yarn as soiled
by fog in the process of spinning.
Dr. LANGDON exhibited specimens of the salt of tech-
nical chlorophyll, which were believed to be the copper salt.
Professor WEISS exhibited raspberry canes bearing a
second crop of fruit, and shoots of the apple bearing a
second crop of flowers. He also exhibited specimens
of a monstrous wallflower, which was considered by De
CANDOLLE to be a separate variety, and named Chezranthus
Chetri, var. gynantherus. The abnormal condition is due to
the transformation of the stamens into carpels which are
often fused round the true ovary.
Mr. P. J. HARTOG read a paper, by himself and Dr.
HARKER, describing a form of apparatus by means of
which they have measured the latent heat of steam. The
authors wish the results, which have so far been very con-
cordant and give a value distinctly lower than that found
by Regnault, to be considered preliminary only, until they
have been able to extend their observations.
A paper on anew sporiferous spike, apparently of the
Calamarian type, from the Lancashire coal measures, by
Messrs. T. HICK and JAMES LOMAS, was also read. The
specimen was found near Oldham.
PROCEEDINGS. 2H
[ Microscopical and Natural History Sectzon.|
Ordinary Meeting, November 3rd, 1893.
mee LLis CUNLIFFE, President of the Section, in the Chair.
Mr. T. A. COWARD and Mr. C. OLDHAM were elected
Associates of the Section.
Mr. ROGERS exhibited specimens of two rare mosses :—
(A) Physcomitrium sphericum, found growing on the mud
margin of the reservoir at Whalley Bridge, the second
locality in England ; (B) Phycomztrella patens, found on the
mud margin of the reservoir at Chapel-en-le-Frith. Both were
found by Professor Barker, late of Owens College, October,
1893. |
Mr. ROGERS also exhibited fine specimens of fruit of
Pyrus japonica, grown at Bowdon.
Mr. CAMERON made a short communication on galls,
and exhibited a gall of the Lzorhzza aptera from the roots of
the birch from Edenbridge ; the birch being a new food
plant, the others, apart from the oak, being beech, pine and
vine. Also an elongated spindle-shaped woody gall on
Ulex nana from Warwickshire. This gall is undescribed,
differing altogether from the other gall on Ulex (Asfondt-
lyza uleces) which is a bud gall. :
ire) COSMO MELVILL, M.A. F.LS., exhibited
specimens of Waulfenia carinthiaca (Jacq.) from South
Tyrol, perhaps the most local of European plants, and
compared it with its nearest allies, both European and
exotic, in the sub-order Digztalee of Serophulariacee, which
were also exhibited.
e2 Mr. T. HIcK AND MR. J. LOMAX ox
On a New Sporiferous Spike from the Lancashire Coal
Measures. By Thomas Hick, B.A., B.Sc., Assistant
Lecturer in Botany, Owens College, Manchester,
and James Lomax.
(Recezved October 31st, 1893.)
The fossil which forms the subject of this communica-
tion was found by one of us at Moor Side, near Oldham,
and has been derived from what is locally known as the
Upper Foot Coal of the Lower Coal Measures, a layer
which is practically identical with the Halifax Hard Bed in
Yorkshire. Unfortunately only a‘single specimen was met
with. From this two sections were prepared, both of which
are longitudinal. One is nearly, but not exactly radial,
except perhaps for a short distance at the base of the spike,
while the other is so tangential as only to meet the axis at
the upper extremity. The following description applies
exclusively to the former section, unless the contrary is
stated, but it contains nothing which is inconsistent with
the other.
GENERAL CHARACTERS.
The section of the spike measures 4 centimetres in
length by 8 or g millimetres in breadth. As if Gegm@e
complete at either end, it was probably somewhat longer
originally. The shape of the spike appears to have been
cylindrical, but whether or not there was a narrowing at the
ends it is impossible to say, nor is there anything to indicate
its position on the parent plant.
Like many other carboniferous fruits it is composed of
an axis and numerous lateral appendages (/zg. 7). The
latter are of two kinds, sterile bracts (Fzg. z, a, 6, f), and
sporangiophores (g, 2), placed at the nodes of the axis in
A New Sporiferous Sptke. 23
alternating whorls. In all 14 nodes, about 2°5 millimetres
apart, can be counted, which originally bore whorls of
sterile bracts, a few of which are present zz szfu in the
section (/zg. z, a, 0). The oumber of bracts in each whorl
cannot be made out with certainty, but it was probably
small, and perhaps did not exceed 6 or 8. This estimate is
based upon the appearance of the uppermost nodes, which
are cut so tangentially that the anterior bracts are seen in
transverse section (77g. 2, 2).
STRUCTURE OF THE AXIS.
The axis of the spike has a nearly uniform diameter
of 1:17 millimetres throughout, and is obviously made up
of.a central cylinder (or stele) (Fzg. 7, s), surrounded by a
bette (772. 7,2), but the structure of the parts is very
imperfectly shown. The stele, 05 millimetres in diameter,
is, in part at least, composed of elongated elements which
here and there bear faint traces of vascular markings. But
the whole cylinder is so black, and the state of preservation
such, as to preclude any decisive statement as to the nature
of these elements and as to whether the centre of the stele
was or was not parenchymatous. At the nodes which bear
the bracts the cylinder widens out a little, but the section
shows no such expansions opposite the sporangiophores,
perhaps because at these points the section is not radial to
these structures. Neither in the case of the bracts nor in
that of the sporangiophores, has any vascular connection
with the stele been met with, but this is no proof that such
did not originally exist, as it may be due to the divergence
of the section from the radial direction.
THE CORTEX.
The cortex, whose thickness is 0°33 millimetres, is
made up chiefly of large cells, elongated longitudinally. In
the hypodermal region, the cells have thick walls and appear
24 Mr. T. HIcK AND MR. J. LOMAx on
to be prosenchymatous, so that their function was probably
mechanical (zg. 2,a@). The inner cortex is made up of
larger and thin-walled cells, and at certain points there are
unmistakable evidences of the presence of canals or much
elongated cells, in some of which are black carbonaceus
contents similar to those met with in the young stems of
Arthropitys and the sterile bracts of Calamostachys Binneyana
(Fig. 2,¢e). At the sterile nodes the cortex is continued into
the bracts in a way which will be described in dealing
with the latter structures. Unfortunately these details
cannot be illustrated by a figure, as they have been made
out piece-meal from an examination of the cortex of both
specimens, and are nowhere met with in combination.
THE SEERILE SpRAGrs
The members of the successive whorls of sterile bracts
appear to have been superposed and not alternate. This is
inferred from the fact that on one side of the spike the
section has passed through five bracts in succession, and on
the other side two successive bracts are superposed in two
places.
The bracts stand out from the axis at nearly a right
angle—having an extremely slight inclination upwards—
for about three millimetres, and then turn upwards
so abruptly that the limb is approximately parallel
to the axis. The only evidence: as to the presence or
absence of cohesion at the base of the bracts is presented
by the uppermost part of the section, which is tangential. It
is not conclusive on the point, but it certainly proves that if
cohesion does occur, it is restricted to the immediate
neighbourhood of the axis, a conclusion, likewise, suggested
by the second section.
As to the structure and form of the base of the bracts,
little that is definite can be made out. The upper part
would seem to consist of narrow,elongated, sclerenchymatous
:
A New Sporiferous Sprke. 25
elements (/zg. 2, 0) continuous with the hypoderma of the
internode above. The lower is composed of a large celled
tissue with thin walls (/7zg. 2, Z), closely resembling that of
the inner cortex and has no continuation of the hypoderma
of the internode Jelow. In one or two instances the
resemblance to the inner cortex is emphasised by the
presence of black masses in the ceil cavities. From the
appearance of the specimen, this softer tissue seems to
have readily separated from the overlying harder part and
to have been easily destroyed. The two layers together
have a vertical thickness of o'5 millimetres at the point of
insertion on the axis.
The limb of the bract is a long slender body and
probably reached to the second whorl of bracts above
(Fig. z, 0). The structure of the limb is very imperfectly
shown, but it seems to be made up of elongated, narrow,
thick-walled elements, something like those met with in the
upper part of the base. Whether or not it possessed a
large-celled tissue like that of the lower part of the base, it
is impossible to say, but it seems doubtful.
THE SPORANGIOPHORES.
The sporangiophores stood nearly, if not exactly, mid-
way between the successive whorls of bracts, and projected
at right angles from the axis. They are not found in the
section however, and our knowledge of their position is
based upon the short processes shown at g, which represent
tangential sections of the basal portion. The section shows
no trace of a peltate dilation of the distal end of the
sporangiophore, an absence which is difficult to understand
had such existed, unless it were remarkably small. For
this reason we are inclined to think that the sporangiophores
were simple columella-like structures. The histology cannot
be made out with certainty, but there appears to have been
a central strand of delicate tissue enclosed in an outer zone
26 Mr. T. HICK AND MR. J. LOMAX ox
of harder and more lignified elements (Fzg. 7, 2). This
strand may have been a small vascular bundle, but there is
no proof of this. As the section in passing more or less
radially through the sterile bracts has missed most of the
sporangiophores, we infer that the latter have alternated
with the former. We have no information as to the number
of sporangiophores in each whorl, but it was probably small.
THE SPORANGIA.
The sporangia were arranged round the sporangiophores,
but the number connected with each and the mode of
attachment is not clearly shown. Where the section of the
spike is radial two sporangia, one above the other, are seen
between two successive whorls of bracts (Fzg. z, 5p.). Where
it is tangential, the appearances point to the presence of
four sporangia for each sporangiophore (/zg. z, #). The
walls of the sporangia are composed of a single layer of
cells, whose inner and radial walls are thickened (/7zg. 3, 0),
In the surface view the cells are elongated and the longi-
tudinal walls exhibit the projecting transverse processes so
often met with in carboniferous sporangia (/zg. z). No
layer of thin walled cells is observable lining the interior,
though this may be due to disappearance. The size of the
sporangia cannot be definitely stated as they seem to have
been cut in all directions, save those which would enable
their principle axes to be measured. The one shown in
Fug. z at the base of the spike has a length of about 1°6
millimetres and a breadth of about o'8 millimetres. The
same is shown enlarged in /7zg. 3, where the point of attach-
ment is probably seen at (a).
THE SPORES.
The spores are all of one size, averaging 0'066 millimetres
in diameter, and are rounded in shape (/zg¢ 3, c). No
A New Sporiferous Spike. 27
external markings can be made out on the walls, nor are
they grouped in tetrads. The wall appears to be thickened,
but this is probably due to the mode of preservation, and,
in most cases, the contents remain as a central black mass,
in which there are occasionally indications of a nucleus.
They were probably mature and not in process of develop-
ment at the time of mineralisation.
SYSTEMATIC POSITION.
Imperfect as the preceding description is, it seems
sufficient to enable us to refer the new spike to the Ca/ama-
veeae rather than to the Lycopodineae, and hence its systematic
position must be sought among the spikes of the former
group. Unfortunately, the internal structure of these spikes
is known in a few cases only, and the attempts to classify
them by external characters alone, has not been very
successful. Hence, any attempt to allocate the new spike
to one of the groups into which the Calamarian fruits are
divided can only be tentative and provisional, but this is
no reason why the task should be avoided.
A comparison of the new spike with the well-known
Calamostachys Binneyana, Schr., which is now known to be
the fruit of some form of Calamites, reveals the fact that
there is a close general agreement between the two,
accompanied by differences of some importance. They
agree in the alternation of sterile and fertile whorls of
appendages ; in the position of the sporangiophores, which
stand midway between the successive whorls of bracts ; and
the number of sporangia associated with each. But the new
fruit differs from Calamostachys Binneyana in the form,
length, and, perhaps, number, of sterile bracts in each whorl ;
in the absence or great reduction of the sheath-like disk
formed by the cohesion of the bracts; and probably in the
absence of a peltate expansion at the distal ends of the
sporangiophores. In addition, the spores are apparently
28 Mr. T. HICK AND MR. J. LOMAX on
slightly larger, but this is, perhaps, of little importance, as
exact measurements are, in most cases, difficult to make.
The precise value of these agreements and differences,
from the systematists’ point of view, is not easy to estimate,
but we cannot be far wrong in regarding the former as of
much greater value than the latter. To us, they seem
sufficient to justify the inclusion of the new spike in the
genus Calamostachys, which, as at present understood, is to
some extent, a collective one. Acting upon this opinion,
we propose that henceforth the fossil should be known as
Calamostachys Oldhamia.
RAN
Wie
A New Sporiferous Speke. 29
EXPLANATION OF THE FIGURES.
PuaTE. Fic. 1. Longitudinal Section of the Spike, three times the
natural size.
s. Central Cylinder or Stele of the Axis.
é. Cortex of the axis.
a, b, f. Sterile bracts.
a. do. cut transversely.
g. Sporangiophores.
h. do. cut transversely.
sp. Sporangia with spores.
Fic. 2. Lxlarged view of the base of the bract f Fic. 1 at its
junction with the axts.
Central Cylinder or Stele of the Axis.
Lnner portion of Cortex of Axts.
Outer do. do.
Upper portion of base of bract.
Lower do. do.
VS & RX
Fic. 3. Sporangia with Spores.
a. Probable point of attachment to Sporangiophore.
b. Wall of Sporangium.
c. Spores.
Fic. 4. Surface view of the Wall of a sporangium.
30 PROCEEDINGS.
General Meeting, November 14th, 1893.
Professor OSBORNE REYNOLDS, M.A., LL.D., F.RS.,
Vice-President, in the Chair.
Mr. R. L. TAayvLor, Science Master, Central Schools,
Manchester, and Mr. HORACE LAMB, M.A., F.R.S., Professor
of Mathematics, Owens College, Manchester, were elected
as ordinary members.
Ordinary Meeting, November 14th, 1893.
Professor OSBORNE REYNOLDS, M.A., LL.D., F.R.S.,
Vice-President, in the Chair.
The thanks of the members were voted to the donors of
the books upon the table.
Dr. HODGKINSON exhibited a species of orchid (Catase-
tum), illustrating the extraordinary means by which
fertilization by insect agency is effected in this group of
plants. Experimental demonstrations with the antennz
were successfully given.
Mr. FRANCIS JONES, F.R.S.Ed., exhibited specimens of
polished white marble exposed on the top of the Grammar
School and at Alexandra Park for one year to atmospheric
influences. The first-named specimen showed a loss of I per
cent of its original weight, and the other a loss of 02 per
cent.; whereas a third specimen kept in a room showed no
loss whatever. The utility of the experiment as a test
of the purity of air and its bearing on the wasting of exposed
marble statues were pointed out.
PROCEEDINGS. 31
Professor OSBORNE REYNOLDS read the following
note “On Mr. HARTOG and Dr. HARKER’S Experiments
on the Latent Heat of Steam at 212° Fahr.” :—
“ Since the publication of Regnault’s experiments in 1848
there has been a general agreement as to the value of this
important constant. And no one, in the meantime, has
pointed out any source of error in Regnault’s work. What-
ever may be the true value of this latent heat an agreement
as to the exact figure is of great importance. Otherwise
by the use of different figures results into which this con-
stant enters are thrown into discord. At the last meeting
of this Society Mr. Hartog brought forward results of some
very interesting experiments which show the latent heat to
be something like 27% less than that obtained by Regnault.
From the description, the experiments had evidently been
‘made with the greatest care and the results obtained from
different experiments are fairly consistent. Any source of
error must therefore be some general loss of heat which would
exercise the same effect on all the experiments. After
hearing the paper it occurred to me that such a loss of heat
must necesarily take place in the experiments from a cause
which appeared to have been overlooked by the author of
the paper. Tothis I now direct the attention of Mr. Hartog,
in the hope he may be able, by removing it, to bring his results
into accordance with Regnault’s. The matter which seems
to me to have escaped the attention of Mr. Hartog is the
cooling effect on the interior tube of his apparatus, by which
the steam passed into the calorimeter, of external radiation
through the walls of his enclosing glass vessel. That this
would cause a loss is certain; what this loss would be depends
on the temperature of the room and on the constants of
absorption of the surface of the interior tube and the glass
envelope.”
Messrs. HARTOG and HARKER replied to Professor
REYNOLDS, pointing out that the loss by radiation could
32 PROCEEDINGS.
only be very small, and nearly, if not quite, negligible, in
their experiments. This loss, moreover, must in each case
be proportional to the duration of the particular experiment.
If, therefore, it were appreciable, other things remaining the
same, the longer the experiment lasted, the lower would be
the value found for L. But this was found not to be the
case. A special experiment had been performed since the
last meeting to test the validity of Professor REYNOLDS’
objection, of which notice had been privately given. The
results obtained confirmed the view expressed by the
speakers.
Mr. LIONEL B. WELLS exhibited a map of the inland
waterways of England and Wales prepared by himself and
Mr. RUPERT SWINDELLS, and read a paper on “The Early
History of the Inland Waterways of England and Wales;
and their present condition, with suggestions for their Future
Development.” He pointed out that the shipping entered
at British ports has increased within fifty years from
10,000,000 to about 130,000,000 tons, and that not one of
the old waterways has secured its due proportion of this
enormous increase of traffic. Of the existing waterways
about 1,222 miles are controlled by railway companies, and
2,468 miles are “independent ;” yet the former group carry
only one-fifth the total tonnage which passes along the
entire system. The more important river navigations are
the Weaver, the Aire and Calder, and the Severn. The
improved sections of these have an aggregate of only 112
miles, yet they carry about one-eighth of the total inland
waterway traffic of England and Wales, and the waterways
controlled by the railway companies, though nine times as
long, carry only 65 per cent more traffic. There are about
126 different lengths of waterways in the hands of about
100 proprietors, and if many of these would amalgamate,
through water routes from east to west and from north to
south could be established. With reference to the map it
PROCEEDINGS. 33
was pointed out that as no complete map of the navigable
waterways of the country could be exhibited at the Inter-
national Congress on Inland Navigation which met in
Manchester in 1890, Mr. WELLS and Mr. SWINDELLS had
privately prepared the one exhibited, which showed that
there are 740 miles of navigable waterways in the country
of the existence of which the compilers of the Government
returns of canals seemed to be unaware. Omitting large
estuaries, the total length of canals and navigable rivers in
England and Wales is 3,790 miles. With scarcely an
exception the sills of the locks are below the navigable
draught of the existing waterways, proving that the founders
of the system looked forward to the ultimate deepening of
the canals.
In the discussion which ensued Mr. FARADAY com-
mented on the fact that it should have been left to the
private enterprise of Mr. WELLS and Mr. SWINDELLS to pro-
duce the first complete canal map of England and Wales,
and contrasted the neglect and imperfections of our own
Government departments in this matter with Continental
Government work, as illustrated by the specimens of canal
maps issued by the French, Belgian, and other Govern-
ments exhibited by Mr. WELLS.
34 PROCEEDINGS.
Ordinary Meeting, November 29th, 1893.
Professor ARTHUR SCHUSTER, Ph.D., F-.R.S., Pigs
- President, in the Chair.
The thanks of the members were voted to the donors of
the books upon the table.
Professor LAMB, M.A., F.R.S., made a communication
giving a mathematical explanation of the mode of propaga-
tion of waves through water by a moving object.
Mr. C. H. LEES read a note on the determination of the
thermal conductivity of water.
Mr. HARRY GRIMSHAW, F.C.S., read a paper “On the
treatment of sewage with basic persulphate of iron under
varying conditions, more especially with regard to results
obtained in Salford.” From the experiments he concluded :—
That the Salford sewage in June, 1893, was, in consequence
of the long-continued drought, about 25 per cent more
impure than the average. That while it is possible to vary
the proportion of precipitants to such wide differences as
exist between night and day sewage, it is not practicable
on the large scale to meet the hourly fluctuations in the
composition of the sewage of an industrial town ; during the
working day, therefore, the maximum amount must be
adhered to. That a too rapid flow through the tanks
involves a greater expenditure of precipitants than is other-
wise necessary, and that a flow of an average of about
10,000,000 gallons, or a maximum of 14,000,000 gallons,
through tanks of a vertical area of Soft. by 7ft. renders
proper subsidence impracticable. That in cases of this
kind the only remedy is either the use of excessive amounts
of precipitants or the subsequent passage of the tank
effluent through a straining filter or through land; which
a
PROCEEDINGS. 35
of the two is most economical being determined by local
circumstances.
A discussion ensued, in which Mr. CorBETT, Mr.
BARTON WORTHINGTON, Mr. WILLIAM THOMSON, and
the PRESIDENT took part.
Ordinary Meeting, December 12th, 1893.
Pais bOLTrOMLEY, D.Sc., B.A., F.C.5., Vice-President,
in the Chair.
The thanks of the members were voted to the donors of
the books upon the table.
The CHAIRMAN referred to the death, since the last
meeting, of Professor TYNDALL, an honorary member of
the Society, elected 1868.
The SECRETARIES reported on the completion of the
Joule Memorial statue by Mr. ALFRED GILBERT, R.A.,
originally promoted by the Council of the Society, and
announced that the surplus funds,tothe amount of 4257.1Ts.,
had been handed over to the Society to be used for the
commemoration of Joule’s name, and that the books and
documents of the Memorial Committee had been given to
the Society for safe keeping.
Professor WEISS exhibited some pieces of wood taken
from some gravel beds near Stockport. The wood was
completely waterlogged and quite soft. Exposed to the
atmosphere it became hard and black, lost its woody
appearance, and showed a conchoidal fracture. It was
36 PROCEEDINGS.
transformed into a substance like lignite,and burned like coal
A discussion on the character of the change in the wood
and on the presence and absence of wood in peat bogs was —
participated in by Mr. C. BAILEY, Dr. BOTTOMLEY, and
Dr. HODGKINSON.
The third part of Dr. W. C. WILLIAMSON’S “ General,
”)
Morphological, and Histological Index” to his collective
memoirs on the fossil plants of the coal measures was read.
A paper by Mr. J. C. MELVILL,.M.A., PS) one?
fenia Carinthiaca, Jacquin,” was also vead ; anda paper “On
the Osmotic Pressure of Solutions of Finite Concentration,”
by Dr. THOMAS EWAN.
Experiments on the Latent Heat of Steam. Ly
Preliminary Experiments on the Latent Heat of Steam
at 100°C. By P. J. Hartog, B.Sc. (Lond. and Vict.)
Assistant Lecturer and late Berkeley Fellow in the
Owens College, and J. A. Harker, D.Sc. (Tubingen)
Berkeley Fellow in the Owens College. Com-
municated by Professor Arthur Schuster, Ph.D.,
F.R.S.
(Rececved December rath, 1893.)
The latent heat of steam at 100°C. has been determined
since the time of Black by a number of observers, Rumford
(im), Ure (2), Watt (3), Despretz (4), Brix (5), Regnault (6)
Favre and Silbermann (7), Andrews (8), Berthelot (9), and
Schall (10).
We quote in the following table the results obtained by
Regnault and subsequent observers :—
Observer. ae Extreme Values of L. Hts Ber: os
Regnault... .. 44 533°3—538'4 (11)| 536°67
Favre and either.
Tan... ° .. 3 532°59—541'77
GIEGWS ... ... 8 530°8 —543°4
Bermelot... ... 3 535°2 —537°2 530°2
Beall |... ...| no details, no details. 522
(1) Complete Works (Boston, 1875), Vol. If., p. 417.
(2) Phzl. Trans., 1818, Part II., p. 385.
(3) Robison’s Mechanical Philosophy, ed. Brewster, Vol. II., p. 5 (1822).
(4) Ann. chim. et phys. [1] 24, ‘P- 323 (1823), and Zrazté elémentatre de
physique, p. 94, et seq. (1825).
(5) ogg. Ann., Vol. LV., p. 341 (1842).
(6) Mémoires de P Academie des Sciences, Vol. XXI. (1847).
(7) Comptes Rendus, Vol. XXIII., p. 411 (1846).
a
Se m “TI
m
“
i
mr
=
ss
=
dS|/+ [oO o
{ok
In Fig. 1,if AB and CD represent the corrections for
the temperatures
t,.+ €,
5} and are
44 Mr. P. J. HARTOG AND Dr. J. A. HARKER om
Regnault and Pfaundler assume that the correction for any
intermediate temperature 7,, corresponding to the abscissa
OE, is represented by the ordinate EF drawn to meet the
straight line BD in F.
For this assumption to be valid two things are.
necessary :—
(1) That the change of temperature of the calorimeter
should not exceed 3° or 4°; this conditions
satisfied both in M. Berthelot’s experiments and
in those performed by us; and
(2) That the temperature of the bodies radiating heat
to the calorimeter should remain approximately
constant.
It is evident that we cannot possibly assume the correction
to be merely a function of the temperature of the calori-
meter, if we suddenly bring a hot body into its vicinity
during the course of our observations. In M. Berthelot’s
apparatus, we do the reverse ; we suddenly take away the
hot burner which was radiating heat to the calorimeter
during the actual observation. It is difficult to see how the
observation of the march of the thermometer after this
removal can serve as a datum for the calculation of the
correction to be applied for the period of actual con-
densation, during which the thermal conditions were so
different.
We proceed to describe the modified form of apparatus
[Fig. 2] which we have adopted in order to be able to use
either of the methods of correction just quoted.
The boiler consists of a flask A, through which the tube
BC passes centrally. The upper end of BC is ground coni-
cally to fit into a hollow cap D, which is itself attached by a
glass rod to the movable bell E. This bell fits loosely intoa »
rim, which is filled with mercury so as to form a lute. The
bell and cup may thus be raised or lowered at will, so as to
open or close the valve at C, through which the steam passes
Experiments on the Latent Heat of Steam.
downwards through CB into the con- ity
densing worm W. At Fa side tube is con-
nected with a condenser, if desirable, by
means of an indiarubber tube fitted with P\L
aclip. Thetube at F is kept open during
the preliminary period; it is shut just
after C is opened, and opened again
just before C is closed, so that at no
period does the internal pressure exceed
that of the atmosphere. The end B of
the tube BC is ground into the upper
end of the condensing worm, of which
the construction differs slightly from
that of Berthelot. The steam in our
apparatus enters the condensing worm
by the straight portion, and not by the
spiral. We found this alteration neces-
sary as, after the closing of the valve, the
air entering the worm tends otherwise
to drive the condensed water back into
BC.
The lower half of A was surrounded by a piece of copper
_ gauze bound on with asbestos string, and the lower portion
of the tube BC was surrounded in Expts. I. II., III. by
asbestos, and in IV. and V. by a leaden steam-coil wrapped
closely round it.
The boiler was heated by a small ring burner, of which
the flame was kept at a perfectly constant height from the
moment of lighting till it was extinguished. The gas was
passed first through a Moitessier glycerine regulator (which
maintains the pressure constant to within a half millimetre
of water), and then through a tap fitted with a long handle
moving in front of a graduated circle.
These precautions are necessary for accurate measure-
ments, as variations in the height of the flame naturally
A
46 Mr. P.J. HARTOG AND Dr. J. A. HARKER oz
cause the radiation to the calorimeter to vary. We were
able to regulate the amount of this radiation at will ; but,
of course, too small a flame made the determination too
slow, too large a flame the initial and final corrections too
high. The calorimeter and its jacket, and the thermometer
were protected from excessive radiation by means of screens
of asbestos board.
The calorimeter itself consisted of a copper vessel
weighing 282 grammes. The general arrangement of the
calorimeter and jacket was practically identical with that
employed by Berthelot.
The stirrer consisted of a ring of copper pierced with
several holes, and moved up and down.on glass guides fixed
into a light wire frame, which served to protect the glass
worm from any accidental blow. It was moved by means
of an electro-motor, and a wheel and crank mechanism.
The thermometer used was one by Baudin, of Paris (No.
12,771, metastatic), divided into j,ths of a degree centigrade.
It was compared with an instrument calibrated by Dr.
Schuster, and compared by him with a thermometer
standardized at the International Bureau of Weights and
Measures at Sevres. It was read by means of a telescope,
and the 2oth part of a division, ze, the zoooth part of a
degree was estimated.
The actual modus operandi was as follows :—The water
was first boiled in the flask with the valve at C closed, and
the steam escaping (not condensed). The thermometer
was read from this time forward at the end of each half
minute. When the march of the thermometer had become
regular for some minutes, the valve was opened and the
exit F closed. The steam then condensed in the worm.
When it was thought that sufficient steam had been con-
densed, the total rise being from 3 to 4 degrees, the exit
was opened, and the valve closed, and thermometric obser-
vations were only discontinued when the march of the
Experiments on the Latent Heat of Steam. 47
thermometer again became regular. The flame was then
extinguished, and the worm was detached, corked, carefully
wiped, and allowed to remain in the balance-case for some
time before weighing. The error on the determination of
the weight of the water condensed in the worm could not
exceed one part in 10,000. We made a special blank
experiment without condensation, to ascertain if the
Regnault-Pfaundler corrections were applicable, and found
this to be the case.
We give below the readings of the thermometer during
one experiment (No. 1).
[The first readings given are those taken after the water
had been boiling for 20 minutes. ]
Time. Reading. Notes.
ih. =m.
4 6 a 14°524
A ae 14°532
4 7 a 14°540
, = a Kees Preliminary period.
GR «ss 14°564
4 9 14°573
AROn <2. 14°582 aad
7S Ke, _— — na) Valve opened, 4h. 9 50%
Mets ay. Ane ce om
ACED 2s 157 o2 2s —
4 114 i, 20 Sie —
A 12 ae -— ... Reading missed.
2 Be ge ee —
Ay 13 se co Oy a —
AS ws 767.22 “ih a
A Td are 16° 46 bbe —
) A 16" Fo ee -—
A a5 eS 16° 93 ace =
a 7° 1c ae —
4 16 Seis r7 40 Jae =
a) ere 07 OA ad —
A 17 we Ly O6 ne —
48 Mr. P.J. HARTOG AND Dr. J. A. HARKER ox
Time. Reading. Notes.
i.) mn.
OLE e a mt ft — :-» . Valve closed.
4 18 a 18°I40 ee —
AAS S02 es — .«. Reading missed.
4 19 sna 18°170 sisi —
AP BOs i! tee 18°176 _— as
4 20 =r 19 19a Hes —
AOR. | ss. 18184 bie —
A 2% iG 18187 sas —
AT a 18192 oes —
A722 ee 18°197
Ae eee |) Sa 18°201
4 23 Be 18°205
A 28R by os tee Final period.
4 24 ee 18°214
A BAe. 6s. 1O'217
4725 sists 18'220
A 25s. te Te228
Rise of thermometer per minute during initial period (4h. 6’ to
4h. 934’) ="0165°.
Mean temperature of initial period = 14°°553.
Rise of thermometer per minute during final period (4h. 22’ to
4h. 254’) = "0074".
Initial temperature of calorimeter (4h. 9’ 50” =14°588°
Final ie a (4h..22'= 18097
DPoas eect = 3°'609
From the above data we can calculate graphically, in the
way described, the correction to be applied for each succes-
sive half-minute of the middle period; and we thus find
that the total correction is o'118°.
The corrected temperature - difference is therefore
(3°609 — O'118) = 3491”.
The other data of the experiment were as follows:—
i St a
Experiments on the Latent Heat of Steam. 49
Sp. ht. Water eqt.
Weight of copper calorimeter... 284°5 0°0933 26°54
‘ RASS SUUTEL cae) pea) OF "086 7°50
Ss glasswormandguides 46°8 “O17 7°87
SMEIMIOMICtEr ... 0 65. wo. wee os: Ba E10
Water in calorimeter (corrected
for GuGyancy in air) .:. ... Ue fe 1717°0O
otal * =| E7007On
Barometer-reading, 762°4mm. B.P. of water=100"07.
Weight of water condensed = 10°122 grammes.
We have then
i pions Line — (100°07 — 18°20)
IO°122
= 525°13 cals.
We give in the following table the experimental details
of five experiments (including the one just quoted).
1. Number of Ex-
PELMMCHE ..5..:... I. i TEE: IV. WV;
2. Water- equivalent
of calorimeter
ameveontents .:. 1760°0 1723°2 1740'2 17434 1681°0
a) Vemperature of
SECAUA, Wi5.2s 0's wre. £LOO.07) | LO0'07 (100°26 160"30 *. 100"00
4. Initial temp. of
Calorimeter ...... 14-509) 13°027 12°968 12'526. 14°948
5. Final temp. of
ealerimeter (7,)... 18°197 17°577 16°330 16°206 16°062
6. Observed _tem-
perature - differ-
CO nloiniaic ve ses 25000) 7 43550. 3302 iO 7S, 1 rr
7. Total correction. —*118 —'I134 —*I27 — °239 —"123
8. Duration of experi-
ment in minutes. 12 15 8 13% 5%
g. Weight of water
condensed, in
SRAMMIMCS 6... s0.00 forlez T2540, O270 | orS54.). 2°742
fon Value of L ...... Ban Gs 52407 52567 524-33 522"°65
Mean value of L deduced from experiments I.—V.=524'60
” F) ” ” I.—IV. = 524°85
In the above calculations we have taken our heat unit as
50 Mr. P. J. HARTOG AND DR. J. A. HARKER on
the amount of heat required to raise one gramme of water
through 1° of the hard-glass mercury thermometer in the
neighbourhood of 15° C.
It will be observed that our results differ from those of
Regnault by more than 2 per cent. We have failed so far
to discover any explanation of this difference, either by
ascertaining an appreciable error in our own work or in that
of the great French physicist. Professor Osborne Reynolds
has suggested that radiation from the inner surface of the
central glass tube must cause a certain amount of conden-
sation on its surface, and that the water so condensed
would run down into the worm, and thereby cause an error
of calculation possibly sufficient to account for the difference
between our results and those of Regnault. The heat
radiated into a vacuum by a square centimetre of glass at
100° has been determined by Gratz (Wzed. Ann., Vol. X1.,
p- 913), and the absorption by glass of heat radiated from a
Leslie cube heated to 100° by Melloni (quoted by Wiillner,
Lehrb. ad. Experimental Phystk, Vol. IIL. p. 197), so that we
can form an estimate of the loss due to this source, and
calculation shows that the loss falls in all. probability well
within the error of experiment. This conclusion is borne
out by the fact that the amount of water condensed by
radiation must be proportional to the duration of the experi-
ment; while a glance at the table shews that, other things
being approximately the same (see ¢.¢. Expts. III. and IV.),
the results of experiments, calculated without taking account
of this correction, are independent of duration. We are,
however, obliged to Professor Reynolds for his criticism,
and shall meet it by making use of metal vessels in the
experiments which are in progress.
It may here be pointed out that the determinations of
Regnault for the latent heat of steam at o° have not been
confirmed by subsequent observers [see Winkelmann
(Wied. Ann., Vol. IX., p. 208, 1880) and Dieterici (zbzd, Vol.
Experiments on the Latent Heat of Steam. 51
XXXVII., p. 494, 1889)]; but on this point no agreement
as yet exists.
It occurred to us that our results might be controlled by
the experiments made by Joly with his ingenious steam
calorimeter. (Proc. Roy. Soc., Vol. XLI., p. 352 (1886), and
Vol. XLVII, p. 219 (1889). By the use of this instrument we
can calculate the specific heat of a body if we suppose the
latent heat of steam to be known, and its author used it for
this purpose ; and, inversely, we can also use it to calculate
the latent heat of steam if we assume the specific heat of
the bodies experimented on to be known. Unfortunately
the specific heat even of bodies like silver, which are easily
obtained in the pure state, is not known with the requisite
accuracy. Thus Regnault gives for the sp. heat of silver
0'05701, Kopp gives 0'056, and Bunsen gives 070559. (The
numbers are quoted from Joly, Proc. Roy. Soc., XLI., p. 358.)
In order to use the Joly calorimeter for our purpose it
is evidently necessary that we should make use of a par-
ticular body of which the specific heat has been determined
immediately beforehand with the water calorimeter. This
we propose to do shortly.
The other means at our disposal for controlling our
numbers is less direct.
A well-known equation in thermodynamics gives us a
relation between
L, the latent heat of steam at the absolute tempera-
fire: a,
(s‘—s), the difference between the specific volumes of
saturated steam and water at T’,
dp the differential coefficient of the vapour tension
dT of water with regard to the temperature, at T°,
and
J, the mechanical ao of heat, namely :—
d;
L=3(¢— S) \o
52 Mr. P. J. HARTOG AND Dr. J. A. HARKER on
The quantities J and s’ are by no means easy to
measure, nor have we space to discuss the values obtained
for them by different observers. There is, however, reason
to believe that the value for J given by Griffiths (PA77.
Trans., 1893, p. 493), viz., 47194 x 10’ C.G.S. units, is within
zoo0 Of the truth. The experiments of Perot (Axx. Chim.
Phys. {6| XIII, p. 159) were performed with extreme care,
and we accept his value for the specific volume of steam at
99'60°C., namely, 1657cc.
We have used two formulae to calculate dp/dT from
Regnault’s experiments, which give results differing by
less than 1 per thousand. That of Moritz gives ds/dT =
3°58574x 10* C.G.S. units; that of Roche gives as/dT =
3758318 C.GS. units, taking ¢=980'67.*
If we calculate out L with the values given, we find that
with Moritz’s number L=527°54 calories, with Roche’s
number, L=527'16 calories, for the temperature 99°60 C.
(which we choose because Perot’s determination was made
at that temperature). At 100° the value of L would be
somewhat less (about half a unit, if Regnault’s interpolation
formula is approximately correct.)
These numbers agree well with the one obtained by us,
viz., 524°8, but at the same time, we should hesitate to
regard this confirmation as conclusive.
* Moritz’s formula, quoted by Wiillner, Lehrbuch der Experimental-Physik,
Vol. IV., p. 683, is as follows :—
log.49 P=at bat—cBt
where p = pressure in 7 of mercury, ¢ = temperature centigrade.
log.49 = ‘006864937
log. 19 P=1°996725536
log, 9 @=2°131990711
log. 49 ¢=0°611740767
&=4°7393707-
Roche’s formula, quoted by Hirn, 7héorie Mécanique de la Chaleur,
T. I., pp-'323, 325, 18 as follows.:—
ip 0°090936948/
d
aT [1+0°'0049528167(20+2)?]
Experiments on the Latent Heat of Steam. 53
We are at present engaged in repeating our determina-
tions with an apparatus made chiefly of metal. In the new
model we have replaced the gas burner by a coil of wire
placed within the boiler, and heated electrically. By this
means, we hope to reduce the radiation to the calorimeter,
and consequently the correction, very considerably, and
thereby to increase the accuracy of our results.
We have, in conclusion, to tender our thanks to
Semessot Schuster and Mr. H. E. Hadley, B.Sc. for
assistance given in the course of our work, and especially to
Mr. S. H. Davies, B.Sc., who took part in a tedious series
of preliminary rough experiments, of which no account is
given here.
54 Dr. W. C. WILLIAMSON ox
General, Morphological, and Histological Index to the
Author’s Collective Memoirs on the Fossil Plants
of the Coal Measures. Part III. By William
Crawford Williamson, LL.D., F.R.S., &c., Foreign
Member of the Royal Swedish Academy ; Corres-
ponding Member of the Royal Society of Gottingen.
(Recetved December 12th, 1893.)
LIST OF WORKS
ON THE ORGANISATION OF THE
FOSSIL PLANTS OF THE COAL MEASURES,
AND GENERAL INDEX TO THEIR CONTENTS.
ROYAL SOCIETY SERIES, I. no XIX:
Symbols. Parts.
A. I. Calamites and suggested genus Calamopitus (not subsequently
insisted upon). Figs. 16 and 17 do not belong to Calamites
but to the subsequently adopted genus Astromyelon.
Phil. Trans.5 187%.
EB; II. Lepidodendron selaginoides, Diploxylon (Corda), Ulodendron,
Favularia, Sigillaria, Stigmaria, Lepidodendroid Cone (?)
ultimately Lepidodendron parvulum. (Memoir XVI.)
Anabathra. hl. Trais., 1872.
C. III. lLepidodendron brevifolium, (Burntisland form) and _ its
Lepidostrobus. Restoration of Lepidodendron. iii.
Trans., 1872.
D. IV. Lyginodendron Oldhamium; Heterangium Grievii. /Phz/.
Trans., 1873.
E. V. Asterophyllites with Sphenophylloid axis. Sphenophyllum.
Volkmannia (now Sphenophyllum) Dawsoni, Strobilus
of Asterophyllites (subsequently Paracalamostachys
Williamsoniana; Weiss) Asterophyllites fruit (subsequently
Palzeostachya pedunculata. (See Weiss. Steinkohlen-
Calamarien). Calamostachys Binneyana, Calamites verti-
cillatus. Root of Asterophyllites (afterwards Amyelon).
Phil, Trans., 1874.
F. VI. Rachiopteris aspera (afterwards petiole of Lyginodendron
Oldhamium) Rachiopteris Oldhamium, Rachiopteris duplex,
Rachiopteris Lacattii, Rachiopteris bibractensis, Anacho-
ropteris Decaisnii. Phz?. Trans., 1874.
G. VII. Myelopteris (Medullosa of Cotta), Psaronius Renaultii, Kalo-
xylon Hookeri (now known to be root of Lyginodendron).
Phil. Trans., 1876.
H.
The Fossil Plants of the Coal Measures. 55
VIII.
LX:
XI.
XII.
AIT.
XIV.
XV.
XVI.
PV EL,
XVIII.
Rachiopteris corrugata, Fern Sporangia, Gymnospermous
Dadoxylon, Gymnospermous Seeds, Lagenostoma ovoides,
Lagenostoma physoides, Conostoma oblonga, Conostoma
ovalis, Conostoma intermedia, Malacotesta oblonga,
Trigonocarpon oliveforme, Hexapterospermun Noggerathi,
Cardiocarpon anomalum, Cardiocarpon compressum, Car-
diocarpon acutum, Cardiocarpon Butterworthii, Polyptero-
spermum. /fzl. Trans., 1877.
Astromyelon, subsequently A. Williamsonis (and now known
to be the root of Calamites), Calamites, Asterophyllites,
Lepidodendron selaginoides, Lepidostrobus, Macrospores,
Rachiopteris cylindrica, Cordaites (?) epiderm, Lygino-
dendron (?) anomalum, Lepidodendroid cortex, Oidospora
anomala, Volkmannia (?) parvula (now Lepidodendron
parvulum), Lepidodendron Spenceri. /z/. Zrans., 1878.
Arran Lepidodendron, subsequently L. Wunschianum, Lepido-
dendron Spenceri, Heterosporous Lepidostrobus, Calamo-
stachys Binneyana, Rachiopteris insignis, Tylosis,
Rachiopteris robusta, Sporocarpon elegans, Sporocarpon,
pachyderma, Sporocarpon' asteroides, Sporocarpon
ornatum, Traquaria, Zygosporites (subsequently shewn
to be spores), Dadoxylon, Lagenostoma ovoides, Cardio-
carpon anomalum, Calcisphera (Radiolariz of Judd)
Rachiopteris di-upsilon. P&z/. Trazs., 1880.
Lepidodendron selaginoides, Lepidodendron Harcourtii. (The
plant so named here is now designated L. fuliginosum.
See Proceedings Royal Society, Vol. XLII., p. 6).
Stigmarian rootlets. Medullary rays of Lepidodendron
selaginoides, Calamostachys Binneyana and C. Casheana,
Fungi. hdl. Trans., 1881.
Astromyelon Williamsonis (now root of Calamites), Psaronius
Renaultii, Zygosporites (in a Sporangium), Calamites,
Lepidodendron, Halonia, Sporocarpon ornatum, Salisburia
Adiatifolia, Phzl. Trans., 1881.
Heterangium Tilizoides, Kaloxylon Hookeri (now root of
Lyginodendron). Phzl. Trans., 1887.
True fructification of Calamites. Phz/, Trans., 1883.
Rachiopteris Grayii, Rachiopteris Lacattii; Calamostachys Bin-
neyana, Rachiopteris hirsuta, Rhizonium verticillatum,
Rhizonium reticulatum, Rhizonium lacunosum.
Lepidodendron fuliginosum, Lepidodendron mundum, Lepido-
dendron Spenceri, Lepidodendron parvulum, Rachiopteris
inequalis. Phzl. Trans., 1889.
Lyginodendron Oldhamium, Bowmanites (Volkmannia) Daw-
soni, now Sphenophyllum Dawsoni, Calamites. 1890.
Bowmanites (now Sphenophyllum) Dawsoni. Rachiopteris
ramosa, possibly R. hirsuta var. ramosa.
** On the structure of the woody Zone of an undescribed form
of Calamite.” Memozrs of the Manchester Literary and
Philosophical Society, 3rd Series, Vol. 1V., Session 1868-9.
**On a new form of Calamitean Strobilus.” J/emozrs of the
Manchester Literary and Philosophical Society, 3rd Series,
Vol. IV., Session 1869-70.
56 Dr. W. C. WILLIAMSON ox
W. ‘¢On some Anamolous Oolotic and Paleozoic forms of vegeta-
tion.” Royal Institution of Great Britain, Weekly Evening
Meeting, Feb. 16, 1883.
2. & ‘*On the relations of Calamites to Calamodendron,” with
description of an intermediate form. Memoirs of the
Manchester Literary and Philosophical Society, 3rd Series,
Vol. X., 1886-7.
v. A Monograph on ‘‘the Morphology and Histology of Stigmaria
ficoides.” Palwontographical Society, Volume for 1886.
Z. *‘On the Structure and Affinities of some Exogenous stems
from the Coal measures.” Monthly Microscopical Journal,
Aug. I, 1869.
AA. ‘**On the Organisation of the Volkmannia (now Sphenophyllum
Dawson).
BB. XIX. Lepidodendron Harcourtii Bromenzart, Halonia, Ulodendron,
Lepidophloios, Lepidostrobi, Lepidodendron Spenceri.
Phil. Trans., 1893.
INTRODUCTION.
The Carboniferous Plants that I propose to deal with in
Part III. of this Index are the Ferns. Seeing that fronds
of this group are so extremely abundant in most of the
shales and sandstones of the Coal measures, it might have
been expected that their stems, branches, and petioles would
be equally so in our calcareous nodules ; but, unfortunately,
this is: not entirely the case; yet they are not wholly,
wanting, but such as we do obtain are usually fragments of
stems, petioles, and the secondary and ternary branches of
fronds. It is extremely rare to find any of these accom-
panied by their leaves or leaflets. Hence, it is often very
difficuit to determine whether or not the objects we are
studying belong to the Filicine group. There are certain
well-known localities where fragments of stems are more
abundant than elsewhere, which stems unmistakeably belong
to the arborescent sections of the semi-tropical ferns. In
these examples their internal organisation is too character-
istic to leave much room for error respecting their primeval
affinities, but there are many forms which leave abundant
room for those differences of opinion respecting their true
relationship that are so common in the writings of even our
The Fossil Plants of the Coal Measures. By)
most experienced observers. Under these circumstances
I strongly object to the undue multiplication of generic and
other names that are so common amongst us. Where we
find considerable groups, the individuals composing which
have certain very definite features existing throughout the
entire group, as is the case, for instance, with that of the
Zygopterids, it seems to me useful to give them a common
name. But the cases are numerous in which this cannot
be done. In such types each example would require a
name of its own. This necessity would arise, partly from
the imperfection of the fragments with which we have
to deal, but also, in part, from the absence, in many
such instances, of sufficiently individualised features to
make their differences easy to define. In such cases as
Lyginodendron and Heterangium these fundamental differ-
ences are important and easily defined ; but in numerous
other instances this is not the case. To these I have
assigned, in my later Memozrs, the comprehensive term
Rachiopterzs, which binds together a number of examples of
which the general organisation is certainly fern-like, but which
signifies nothing more. As more definite groups can be
formed out of this very varied and comprehensive cluster,
such groups can be differently dealt with. With the
working of this method we have a good illustration in one
of the earliest plants that came into my hands, which I
had described in Part VI. of my Wemozrs under the name
of Edroxylon, but to which I afterwards assigned the name of
Rachiopteris aspera. In my Part IV., I had described a
very distinct plant under its present name of Lyginodendron
Oldhamium ; but in Part VI. I expressed my strong con-
viction that the former plant would ultimately prove to be
the petiole of the latter one. I never lost sight of this
possibility, but I had to wait sixteen years before I
obtained clear proof that my original surmise was absolutely
correct. This determination was an important one, because
58 Dr. W. C. WILLIAMSON oz
Lyginodendron was a plant with a magnificent zone of
secondary exogenous wood, developed from a true cambium.
But Dr. Scott and I have recently united with it a second |
form viz.,the Kaloxylon Hookeri, which proves to be its root. “e
No true fern previously discovered had exhibited such a
cambium; but the Lygznodendron Oldhamium described
now took its place, along with the Calamztes and the Lycopods,
in both of which important groups of C7yptogams the
possession of an active cambium was the normal condition.
This family of the Lygznodendra is the first that I propose
to deal with in this part of the Index.
PIBICES:
TYPE OF LYGINODENDRON OLDHAMIUM.
Primary Branch prior to emergence through Cortex.
Earliest State. Transverse.
No Medullary Cavity occupied by primary Wood.
R.—p. 92, Fig. 10, C.N. 1885A.
a. Tracheids of Primary Xylem.
b. Secondary Fascicular Xylem.
Secondary State.
R.—p. 92, Fig. 11, C.N. 1885H. Primary Xylem broken up into about
five separate bundles, a’, a’. See also C.N. 1138.
Medullary Rays.
R.—p. 92, Fig. 10, C.N. 1885A.
p. 92, Fig. 11,/C.N. 18S5H.
BRANCH EXTENDED BEYOND THE CORTEX OF THE PARENT STEM, AND
INVESTED BY ITS OWN CORTEX.
R.—p. 93, Fig. 12, C.N. 1141. Medullary cavity further enlarged,
and filled with medullary cells.
SECONDARY XYLEM.
R.—p. 92, Fig. 12, C.N. 1141. New Trachez to the periphery of each
of the secondary Lamine.
CoRTEX—YOUNG.
R. 1141. Irregular Cambium at the innermost border of the Cortex.
CORTEX MORE MATURED.
Cambium not previously figured or described.
Innermost Cortex of O.N. 1141, 1193, 1194, and 1195.
The Fossil Plants of the Coal Measures. 59
CorRTEX—MIDDLE.
R.—p. 90, Fig. 3c, C.N. 1138.
Gum-Canals.
R.—p: 90, Fig. 3b, C.N. 1138. Fig. 2A 2l.
CoRTEX—EXTERNAL,
R.—p. 90, Fig. 3b, C.N. 1138.,
fibrous Cortical Bands.
Transverse.
R.—Figs. 4a and 5a, C.N. 1138. Figs. 1g and 3g.
Parenchymatous spaccs. Like R.—Fig 6f.
R.—p. 90, Figs. 1f and 3f. p. 91, Fig. ghh’ and f.
D.—p. 385, Fig. 10, C.N. 1113.
LONGITUDINAL, RADIAL, AND TANGENTIAL.
MEDULLA.
Radial not Figured.
See C.N. 1124 and 1982.
PRIMARY XYLEM.
Not distinguishable in long sections.
! SECONDARY XYLEM.
Tangential,
D.—p. 385, Fig. 15k’k”. See 1184.
TRACHEIDS OF PRIMARY AND SECONDARY XYLEM.
Tangential Surfaces.
D.—p. 380, Fig. 4, C.N. 1167.
Radial Surfaces.
D.—Fig. 9, C.N. 1183.
MEDULLARY Rays.
Tangential Sections.
D.—p. 382, Fig. 8. See C.N. 1184.
Radial Section.
D.—Fig. 9, C.N. 1183.
CORTEX.
Tangential of outer layer.
D.—p. 385, Fig. 13, C.N. 1146.
R.—p. 90, Fig. 6, C.N. 1144.
Periphal Surface.
See C.N. 1205 and 12072.
Casé of the above Surface.
See C.N. 1206 and 1207.
PERIPHERAL APPENDAGES TO THE CORTEX.
R.—p. 91, Fig. 6h, h’, h”, C.N. 1144.
Fig. 8hh. Fig. ghh’.
60 Dr. W. C. WILLIAMSON oz
LARGE CORTICAL TRACHEZEAL BUNDLES.
Varied conditions.*
Transverse,
Double type, without secondary xylem.
D.—p. 383, Fig. 17z, C.N. 1187.
Single type, wzthout secondary xylem.
oN. 211d.
Double type, wzth secondary xylem.
One wzth and one without secondary xylem.
CAN. aia:
Both Bundles, wzth secondary xylem.
D.—p. 387, Figs. 19, 20, C.N, 1134.
Single type, wth secondary xylem.
pee CIN. 1293.
FERN PETIOLES, PRIMARILY RACHIOPTERIS ASPERA. WILL.
Of these I have sections from the broad bases, and
from the ultimate twigs bearing the leaflets.
BASE OF PETIOLE.
Transverse.
f.—p. 670, Wie. 1, C.N. 1575p. G82, Mic. by CN. ite.
SMALLER BRANCHES.
R.—p. 90, Fig 2, C N. 1854.
Transverse.
R.—p. 90, Fig. 1, C.N. 117. p. 91, Fig. 7, C.N. 1191,
F.—p. 682, Fig. 7. See C.N. 119*, p. 682, Figs. 8and 9, See C.N.
135, 1191 .Q
Longitudinal.
F.—p. 680, Fig. 2. See C.N. 124, 125, 127’. R.—p. 91, Fig. 8, C.N.
1856. See also 1855.
* The number, arrangements, and forms of these are most easily studied in fairly perfect
transverse sections of the stems, in which we find seven modifications. I have noted their
characteristic features in seventeen such sections. They are most commonly grouped in
pairs, located in the innermost cortical zone, each pair being in more or less close contact.
The above seventeen sections have furnished twenty-eight examples in this condition. Some-
times we find solitary bundles, but such are otherwise undistinguishable from the twin ones.
Of these I have recorded nine in the seventeen sections. We occasionally find a pair, one
of which is in its normal condition, but where the peripheral surface of the second one is
furnished with a variable number of secondary trachezal laminz arranged in a fan-shaped
manner. In three instances I have found both the bundles so furnished, and in three
examples I have seen the solitary bundles similarly supplied on their external borders. In
nearly all the cases where the bundle of primary trachez has a zone of secondary xylem on
its peripheral side I have found a zone of cambium investing its outer surface. In one instance
the bundle must have been imbedded in the cambium, because the secondary laminz radiate
equally in a star-like manner from the entire periphery of the primary bundle. We occasion-
ally find the pair being pushed outwards through the outer cortex of the stem or branch. In
such instances the two bundles are always imbedded in a considerable development of cortical
parenchyma, which is obviously about to escape as a branch from the periphery of the parent
stem. But this is a point that will require a more detailed examination later on—a point that
involves the entire question of the position of the Filicinz during the Carboniferous age.
The Fossil Plants of the Coal Measures. 61
TRACHEIDS.
F,.—Fig. 3, A, B,C. C.N. 128,
CORTEX.
Dp Ool, big. 5. See C.N. 149, 150, 151.
me 662, Fig. 11, C.N. 142.
p- 681, Fig. 4, 5 (erroneously numbered Fig. 3 in the text).
TERMINAL TWIGS AND FOLIAGE OF PETIOLE.
F.—p. 683, Fig. 13.* See a similar example in C.N. 143.
STRUCTURE OF INDIVIDUAL LEAVES.
See 193a and 1856.
DOUBLE BUNDLES ESCAPING THROUGH THE CORTEX, TO BECOME VASCULAR
BUNDLES OF LEAF PETIOLES (RACHIOPTERIS ASPERA) OF LYGI-
NODENDRON OLDHAMIUM.
R.—p. 89, Fig. 1, k. C.N. 1880. See also C.N. 1890 and I150.
C.N. 1980 (another section).
C.N. 1981. A second section from the specimen 1980, but in which
the pair of bundles and their appropriate investments have
become almost completely detached from the parent Lyginoden-
dron, and become an ordinary example of the Rachiopteris
aspera. Thus, since the latter condition is a true fern frond,
we now know that at least one of the carboniferous ferns possessed
a true cambium by which was developed an elaborate zone of
exogenous secondary xylem possessing conspicuous medullary
rays.
HETERANGIUM GRIEVII. Will.
This plant approximates so closely to Lygznodendron in
most features of its structure as to convince me that they
belong to the same division of the fern family. Their
distinctions are chiefly seen in the arrangements of the
tissues which occupy the interior of the medullary cavity.
Instead of finding the primary xylem, in its young state,
entirely filling that cavity, and ultimately breaking up into
about five very distinct masses, each of which adheres
closely to the inner margin of the secondary xylem, as is
the case with Lygznodendron, that central area of the stem
is partially filled with very numerous small bundles of
primary xylem, the intervals between which are firmly
occupied by a network of what apparently ought to have
been true medullary cells ; notwithstanding the peculiarity
of their position and arrangement, I venture, as I did in the
* The original of this figure is in the Cabinet of my old friend, Mr. J. Butterworth, of
Shaw, near Oldham.
62 Dr. W. C. WILLIAMSON oz
very similar condition seen in the axial centre of Lepzdo-
dendron selaginoides, to apply to these cells the term
medullary.
PRIMARY XYLEM AND MEDULLARY PARENCHYMA.
Transverse.
D.—p. 395, Fig. 30a, C.N. 1250.
p.' 395, Fig. 31b andic, ‘CIN 12co.
Longitudinal.
D.—p. 395, Figs. 32 and 33b and c, C.N. 1266, 1268, 1270, 1276,
1278, 1284.
STRUCTURE OF TRACHEIDS. ;
D.—p. 395, Fig. 24, C.N. any of the above longitudinal sections.
SECONDARY XYLEM.
Transverse.
D.—p. 395, Fig. 30d, C.N. 1250.
Longitudinal,
D.—p. 395, Fig. 32d, d. C.N. 1250.
MEDULLARY RAYS.
Tangential.
D.—p. 396, Fig. 332,.C.N. 1265, Fic: 33, C.IN: 1268.
Radial.
p. 396, Fig. 33f, C.N. 1268.
CORTEX—INNERMOST ZONE.
Transverse.
D.—p. 396, Fig. 30g and 35g, C.N. 1250.
Longitudinal,
D.—p. 397, Fig. 32g, C.N. 1270.
MIDDLE ZONE.
Transverse.
D.—p. 397, Fig. 3oh, C.N. 1250. Fig. 35h’.
Longitudinal,
D.—p. 397, Fig. 45, C.N. 1270. Fig. 32hh, C.N. 1278.
LARGE VASCULAR BUNDLES IN INNER AND MIDDLE CORTEX.
Transverse.
D.—p. 399, Figs. 30 and35 m.m’. Figs. 37 to 44, C.N. 1240 to 1247-
Longitudinal.
D.—p. 399, Fig. 32m, C.N. 12849. See also 1248 (barred).
ORIGIN OF BUNDLES.
D.—p. 4o1, Fig. 30m’, C.N. 1250.
ANOMALOUS BUNDLE WITH SHORT TRACHEIDS.
D.—p. 401, Fig. 36, C.N. 1260.
a
The Fossil Plants of the Coal Measures. 63
OUTERMOST CORTEX.
Transverse.
D.—p. 398, Fig. 35. See C.N. 1244k.”
Longitudinal.
Dp. 208. Fig. 32k”, C.N. 1278k”.
Youne Twices.
Transverse.
D.—p. 402, Fig. 46, O.N. 1244, 1280, 1283, 1295, and 1296.
Longitudinal.
D.—p. 42, Fig. 47. See numerous sections in C.N. 1287 and in C.N.
12964.
HETERANGIUM TILIAZOIDES. Will.
This plant approaches so closely to WH. Grzeviz, not only in
the general type of its structure, but even in many of the
details of its organisation, that I see no reasonable grounds
for placing them in separate typical groups. At the same
time, as I have shown in my Memoir XIX., notwithstanding
its typical resemblances to H. Grzevzz, and though the differ-
ences between the two are those of detail, and not of type,
the beautiful structures of A. Tzlzewoides show a distinct
advance to a higher order of exogenous organisation than
we find in the former plant. ‘So far as its central vasculo-
medullary axis is concerned, it is a true Heterangzum in
every detail characteristic of the genus; but when we turn
to the aspects of its secondary xylem, and its investments
of highly developed Phloem, we discover the differences
between the two forms. This is important. Lygznodendron,
now clearly proved to bea true fern, carries inseparably
along with it Heterangium Grievzz, and in like manner the
latter cannot be disjoined from H. Tz/wozdes. If all this is
incontrovertible, it results that the fern must now be
regarded, not only as ranking amongst the exogenous
Cryptogams, but as taking a high position in that well-
characterised group.
STEM OR BRANCH.
Transverse.
Nic —p. 289,) Fig, 1, C.N. 1302.
64 Dr. W. C. WILLIAMSON on
MEDULLARY AXIS AND ITS PRIMARY XYLEM.
N.—p. 289, Fig. 1A. Fig. 3a Medullary Cells, 3b Primary Xylem.
p. 289. Fig. th. - Fig. 2B, CoN. 1303.
N:—p. 289, Fig. 5, b.c and b.c.,* CN. 1303:
N.—p. 389, Fig. 4d secondary vascular laminz ; 4h secondary medullary
rays, C.N. 1303.
N.—p. 389, Fig. 4g,g extensions of primary medullary rays. See also
Fig. tg, C.N. 1302.
Longttudinal.
Radial.
N.—p. 291, Fig. 9, including secondary xylem and cortex, C.N. 1628.
p- 291, Fig. 9A, vasculo-medullary axis. a, medullary cells; 4,
tracheids of primary xylem.
p- 291, Fig. 9B; d,d, secondary xylem; h,h, medullary rays.
PHLOEM ZONE C.
Transverse.
N.—p. 290, Fig. 1C, C.N. 1302.
p. 290, Fig. 1k, defined Phloems of separate Vascular bundles.
C.N. 1302. See also Fig. 5k, C.N. 1303, and 4k.
PHLOEM RAYS.
N.—p. 290, Fig. mn, C.N. 1302; p. 290, Fig. 2n, C.N. 1303; p. 292,
Fig. 13n, C.N. 1619; p. 290; Fie.4n,n, CN. 53035
CORTEX, INNER.
Transverse.
N.—p. 290, Fig. Ip, C.N. 1302.
p. 290, Hig. 2p, C.N: 1303 = ps 290, igs 3p, CANeer-
PHLOEM ZONE AND INNER CORTEX.
Longitudinal. Radial.
SECONDARY MEDULLARY RAYS.
N.—p. 291, Fig. 9hh, C.N. 1628.
PHLOEM RAYS.
Transverse.
N.—p. 291, Fig 4n,n.
Longitudinal.
N.—p. 291. Fig. 9cn, C.N. 1628.
PHLOEM TUBES—SIEVE TUBES OR CAMBIFORM CELLS.
N.—p. 291, Fig. ol, C.N. 1628.
PHLOEM.
Tangential.
N.—p. 291, Fig. tol (Sieve tubes ?), C.N. 1622.
* Two bundles pushed outwards from their normal position as a regular portion of the
secondary xylem cylinder.
The Fossil Plants of the Coal Measures, 65
_ INNER CoRTEX.
Radial,
N.—p. 291, Fig. 9D, C.N. 1622.
OUTER CORTEX.
Transverse.
N.—>p. 290, 291, Fig. 6r, C.N. 1303. Fig ir, C.N. 1302.
Radial.
N.—p. 292, Fig. 11, C.N. 1304.
MEDULLARY CYLINDER.
Transverse.
P.—p. 156, Fig. 2b, C.N. 1833 ; p. 156, Fig. rbb.*
AERIAL ROOTLET BUNDLES.
Transverse.
P.—p. 157, Figs 1 and 3. Seen in most of the transverse sections.
EPIDERMAL HAIRS.
P,—p. 158 and the Longitudinal section, C.N. 1857.
TRACHEIDS OF MEDULLARY CYLINDER.
All barred. See 1842 x and 1843 x.
CORTEX.
Mixture of Parenchyma, C.N. 1840, and Prosenchyma, C.N. 1841.
ZYGOPTERIS.—Petioles only preserved.
ZYGOPTERIS CORDA.
During the last twenty years numerous organisms have
been described under the name of Zygopteris. Most of
these have been fern-like petioles. In 1889, Professor
Stenzel, of Breslau, published a Wemozr “On the Stem ofa
Carboniferous Plant,” to which he gave the name of Zygop-
teris scandens, but which he placed in a secondary division
of the Zygopteroid group (Ankyopterzs). Ihad previously (in
1888), figured one under my type-name of Rachiopteris Grayiz.
Dr. Stenzel having sent me a copy of his WZemozrs, I arrived
at the conclusion that our two plants were identical. In
order to obtain his opinion on the matter, I sent him one of
my sections of Rachiopterzs Grayzz for comparison with his
* There is still some obscurity in the relations of rb’ to 2b’. Is the latter a modified con-
dition of the former, or is it identical with the axil-sprosse of Stenzel, Fig. 3b, the Zygop-
teriod petiole being wanting ?
66 Dr. W. C. WILLIAMSON om
own plant. Owing to some differences in the dimensions
of the two forms, he was unable to conclude that they were
identical. The petioles of both examples being alike fur-
nished with the characteristic Zygopterozd vascular bundle,
I shall, for the present, continue to follow his example, and
recognise my form under the more definite type-name of
Zygopterts. The first specimen of this type which came
into my hands I published in Wemoir VI., under Corda’s
name of Axachoropteris Decatsnzi, its peculiar Zygopteroid
petiolar bundle not having been discovered at that time.
This, however, has now been done; and since has given
the name of Zygopterzs to a characteristic example of this
group of stems. I have elected to follow his example, and
to apply the same type-name to the entire Zygopterozd group.
RACHIOPTERIS. Will.
Z. BIBRACTIENSTS. Renault.
Transverse.
F.—p. 697, Fig. 49, C.N. 195. For more perfect specimens see O.N.
196A and 197.
Longitudinal.
F. p. 697, Fig. 50, C.N. 108. See also C.N. 1815.
ISOLATED CLUSTERS OF SEMI-SCLEROUS CELLS, APPARENTLY CORRE-
SPONDING TO FIG. 32H OF HETERANGIUM GRIEVII.
N.—p. 291, Fig. 11,t,t,t. C.N. 1304.
VASCULAR BUNDLES, PASSING OUTWARDS THROUGH THE CORTEX,
RESEMBLING THOSE OF D, Fic. 17Z, IN LYGINODENDRON, AND D,
Fic. 35M’M, IN HETERANGIUM GRIEVII.
N.—p. 290. Fig. tu’,u.’ C.N. 1302. Fig. 7u,u, C.N. 1623. Fig. 8u,u,
1302.
SPECIAL BUNDLES, RESEMBLING D, FIG. 7, AND X, Fic. 24, IN LYGINO-
DENDRON, AND D, FIG. 36, IN HETERANGIUM GRIEVII.
N.—p. 292, Fig. 12w, C.N., 1622, and Fig. 13eee’. Fig. 13,e,e,w,
C.N. 1619.
STRUCTURE OF TRACHEIDS.
N.—Barred, p. 293, Fig. 14, C.N. 1301.
Reticulate, p. 291, Fig. 9, 1628. :
\
Bordered Pits, p. 293, Fig. 16, C.N. 1621, | and i
= |
The Fossil Plants of the Coal Measures. 67
ZYGOPTERIS GRA YII.*
MEDULLA.
Transverse.
P.—p. 156, Fig. 12, C.N. 1832. The medullary ce//s have disappeared.
See also 264a. Medullary cells preserved in C.N. 1919D.
ZYVGOPTERIS LACATTI. Renault.
Transverse.
F.—p. 696, Fig. 45, C.N. 201. p. 296, Fig. 47, C.N. 214.
Longitudinal,
F.—p. 696, Fig. 43, C.N. 212. Tracheids barred.
For secondary branches passing off from the primary axis consult
C.N. 1808 to 1812; for barred and recticulate tracheids in the
same bundle see C.N. 1812.
ZYGOPTERIS DI-UPSILON. Wil.
Transverse.
K.—p. 537, Fig. 90, C.N. 216.
Longitudinal.
K.—p.538, Fig. 91, C.N. 218.
For longitudinal sections of Fig. 90c see C.N. 220¢.
Ditto Fig. 9of see C.N. 210f.
Ditto Fig. 90h see C.N. 218, 220, and 221th.
RACHIOPTERIS. Will.
This group comprehends a number of apparent fern
structures, from amongst which no very definite sub-
divisions can be established worthy of having assigned to
them distinctive names. They will, therefore, retain their
present provisional name of Rachzopterzs, until more can be
ascertained respecting their several mutual relations.
RACHIOPTERIS INSIGNIS. Will.
A rare type, the Tracheids of which are very liable to
be filled with Tylosa.
Transverse.
K.—p. 506, Fig. 19, C.N. 265. Fig. 20, the central vascular bundle of
Fig. 19 further enlarged.
p. 506, Fig. 22, Tracheids devoid of Tylose, C.N. 267.
Longitudinal.
K.—p. 506, Fig. 21, C.N. 265. See also C.N. 266B.
Transverse.
p. 507, Fig. 23. Section of the bundle of a secondary branch
issuing through the Cortex of Fig. 21.
* In memory of my old and distinguished friend, Asa Gray.
68 Dr. W. C. WILLIAMSON on
RACHIOPTERIS ROBUSTA. Will.
A rare form, of which I have only two sections taken
from the same specimen.
K.—p. 505, Fig. 23A, C.N. 269-270.
RACHIOPTERIS ING@QUALIS. Will.
Accidentally called A. zrregularzs in the text of Q.
Q.—p. 206, Fig. 28. See C.N. 265b, 320 & 1814.
RACHIOPTERIS CYLINDRICA. Will.
Transverse.
I.—p. 350, Fig. 80, C.N. 179.
p- 351, Fig. $7, C.N. 179; p. 351, Fig. 38, C_N. 179;
Longitudinal.
Dp. 351, Fig. 86, C.N. 182,
RACHIOPTERIS ROTUNDATA.
Anachoroptis rotundata Corda.
I.—p. 350, Fig. 79, C.N. 271. See also 272 and 273.
RACHIOPTERIS GONIOCENTRA. Will.
C.N. 274 and 275. Not yet figured.
RACHIOPL ERTS DOPLLILXG
A very distinct form, only obtained hitherto from the
Burntisland or Petticur district.
VASCULAR AXIS.
Transverse.
F.—p. 688, Fig. 28, C.N. 223, > a,a, Fig. 30, C.N. 237. Fig. 35,
ete CO Ne NG 227
Loneztudinal.
p- 688, Fig. 29, C.N. 234. See also 232 and 244.
SECONDARY PETIOLES.
Transverse.
See Figs. 35A to 35K.
P.—p. 693, Fig. 39, C.N. 240. Fig. 41. Figs. 35D, 35E.
Longitudinal.
See C.N. 239, 242, and 243. Tracheids reticulated.
The Fossil Plants of the Coal Measures. 69
CORTEX.
Transverse.
Most of the specimens.
Longitudinal.
See C.N. 229 to 236.
The specimens from which Figs. 35A to 35K were drawn are in the
Cabinet of Wm. Carruthers, Esq., of the Natural History
Museum, Cromwell Road, London.
ZYGOPTEROID PETIOLE, VASCULAR BUNDLE.
P.—p. 157, Fig. 3f, C.N. 1831.*
AXIL-SPROSSE OF STENZEL.T
P.—p. 156, Fig. 3e and Fig. 5a, C.N. 1831.
RACHIOPTERIS OLDHAMIUM.
Transverse.
Matured.
F.—p. 685, Fig. 20. See C.N. 160. Very young twigs.
Hades, Mics. 22,23. 24. See 160 and 167,
p. 685, Fig. 21, C.N. 160. Rather more advanced.
p- 686, Fig. 25A, see C.N. 150, ‘4° C.N. 156, with a triangular
bundie.
p. 686, Fig. 26. With two secondary bundles becoming detached
from the primary one.
Longitudinal.
p. 686, Fig. 27, C.N. 162.
p- 220, Fig. 30, C.N. 1471. ©
* It is possible that this plant may only be a variety of Rachiopteris hirsuta.
t+ When Memoir VIII. was published I was under the impression that each of these
sporangia possessed an annulus. This is probably true of the rare form, Fig. 25, though I
have no certain evidence that this was the case; but it is not true of the more common York-
shire and Lancashire form, Figs. 27—30.
72 Dr. W. C. WILLIAMSON ox
SPORANGIA; AN APPARENTLY DISTINCT FORM.
p. 220, like Fig. 25, C.N. 1879. Cells of Sporangial wall
much smaller. See C.N. 319a and 318.
Several sporangia like Fig. 25, C.N. 318.
Several sporangia, one evidently pendunculate, C.N.3109.
MYVELOPTERIS. Renault. MYELOXYLON. Brongniart.
Few fossil plants have been the subjects of more con-
troversy than those figured in my Memozr under the first of
the above names. The Medullosa of Cotta, the Palmacites
of Corda, the Stenzelia of Goeppert, to the two names at
the head of this paragraph, including the new Rachiopteris
Williamsont of Seward,—this group has not only received
a confusing number of names, but the question of its
position in the vegetable kingdom has led to its being
tossed to and fro between the Cycads and the Ferns. In my
Memoir referred to above, I described a series of specimens
in my Cabinet, numbered from C.N. 276 to 305. M. Renault
at the same time was, unknown to me, studying similar
objects ; we finally and independently arrived at the same
conclusion, viz., that they were Carboniferous representa-
tions of the living group of Marattiaceous ferns. At a later
period my old pupil, Mr. Seward, undertook a re-examina-
tion of my specimens, and found amongst them what
appeared to be examples of two different forms. One of
these he regarded as being true J/yelorylons, and the
others as belonging to a more ordinary type of ferns,
which he determined to publish under the name of
Rachiopteris Williamsont. ‘The first result was the publica-
tion, in the Azzals of Botany, for March, 1893, of a memoir
on the Myeloxylons, which he regarded as constituting an
independent type of plants intermediate between the Ferns
and the Cycads, but apparently having a nearer relation to
the latter than to the former family.
Under these circumstances, in reply to my request, he
The Fosstl Plants of the Coal Measures. 7%
has kindly given me the following outline of his views on
the structure of his R. W2llzamsonz :—
“The structure of the petiole of Rachiopleris Willtamsont
“resembles in many respects that of AZyeloxylon ; but the vascular
‘bundles show certain well-marked peculiarities, and a divergence
“from those of Brongniart’s genus Mye/oxylon, which seems to
“justify a specific separation. Mdyeloxylon agrees with Cycads
“rather than with Ferns. acheopterts Williamsont approaches
“much more closely to the typical fern-bundle, and is, therefore,
‘regarded as a fern petiole.
“The two plants agree in (1) the nature of the hypodermal
“tissue, consisting of alternating bands of sclerenchyma and paren-
““chyma; (2) in the possession of larger gum (?) canals in the
‘“sround tissue. ‘Their most important differences may be briefly
“stated as follows :—
“In Myeloxylon the bundles of vascular tissue are collateral,
‘Cand the protoxylem is placed next tothe phloem ; in Rachiopteris
““ Williamsont the bundles are concentric, and they agree in
“position with that of the ferns. In Myeloxylon there are no
*‘ parenchymatous elements associated with the xylem vessels. In
“R. Williamsont there is much xylem parenchyma; another
“marked difference consists in the occurrence of regularly disposed
“canals surrounding the xylem in &. Williamsont. These do not
“occur in Myeloxylon. The specimens which have been examined
“of the new species show these canals in various stages of
“development. They are quite distinct from the larger canals
*‘scattered in the ground tissue, and are regularly arranged
‘towards the periphery of the phloem in each bundle.”
Some of the differences here recorded are easily seen.
Others are not so clear in my specimens. Of course the
most conspicuous one is the existence of collateral bundles
in one case, and of circumferential ones in the other. But
even here we must remember that we have collateral
bundles in ferns (¢g., Osmunda), and De Bary has found
circumferential ones ina Cycad. Hence, the question arises,
did these differences always possess the same distinctive
value that they may do now? Schenck and Solms-Laubach
7A The Fossil Plants of the Coal Measures.
differ even now on this point. Hence, I cannot conclude
that these distinctive features settle the question of the
boundary lines between the Ferns and the Cycads. For the
present, however, I have arranged my specimens in Seward’s
two groups, to facilitate their further investigation and
study.
MVELOPTERTS.
PRIMARY PETIOLL.
Transverse.
G.—>p. 3, Fig. 1, C.N. 276. See also C.N. 286, 286b)> 26Genmeeus
very large Petiole from Autun.
SECONDARY DIVISIONS OF PETIOLE.
Pe 3, Figs. 3, 4, and 4*. See 286a and others from C.N. 286 to
202.
Longitudinal.
Primary.
p- 3, Fig. 2, C.N. 298—303.
Secondary.
p- 3, Figs. 5and6. See C.N. 286, 293 and 4.
Oblique.
G.—See C.N. 286e.
SUB-EPIDERMAL SCLERENCHYMA.
Transverse.
C.N. 276. See also 305.
Longitudinal,
C.N. 276f, ¢.
RACHIOPTERIS WILLIAMSONI. Seward.
Transverse.
C.N. 277 to 282. Five transverse sections from the same entire
Petiole.
Longitudinal.
C.N. 283, 284, 285. Three sections from the same Petiole as the
transverse ones.
Memoir VII. Figure 7 is a transverse section of a vascular bundle of
this plant.
Wulfenta Carinthiaca, 75
Notes on Wulfenia Carinthiaca, Jacquin. By James
Cosmo Melvill, M.A., F.L.S.
(Recetved December 12th, 1893.
or many years this beautiful member of the natural
order Scrophularinee has maintained its prestige as the
most local, perhaps, of European plants, if we except the
Dioscorea pyrenacca, Bubani, from the P. de Gavarni,
Eastern Pyrenees.
To those who have read what may be called the ‘ Pioneer
Guide-book’ to the Dolomites and Tyrol, the name of Wuz-
fenia will be familiar, for Mr. G. C. Churchill, who
collaborated with the late Mr. Gilbert in the production of
this work,* based upon three successive visits in 1861-63,
to what was till then a ‘terra incognita’ almost, to the tourist
or botanist, made the search after this plant one of the
chief aims of his journeys. Twice were the travellers
disappointed at finding it past flower, but the third time they
were fully rewarded. The following notes, written by my
brother, the Rev. A. H. Melvill, and my sister, Miss Evelyn
Melvill, who spent four months in the Tyrol this summer
(1893), may be interesting :
We left Lienz on Tuesday, July 25, by an early train for Greifenburg.
With very great difficulty we succeeded in procuring a carriage to drive us to
Hermagor, a distance of about 15 miles. Arrived there we had also great
trouble in finding rooms, as the Post Hotel was full. At length we found
some in the small hotel opposite the Post, where we were made exceedingly
comfortable. We made enquiries first thing about the Wudfenza, and found
the landlady knew all about it, in fact had dried specimens, and showed us in
the garden some living plants, but out of flower. She said she would engage
a guide for us, and afterwards, while we were talking to him and making
arrangements for an early start the next morning, a German gentleman came
* The Dolomite Mountains, by Josiah Gilbert and F. C. Churchill, F.G.S.
London: Longmans. 1864.
76 Mr. JAMES COSMO MELVILL ox
up who knew all about the subject, the best localities, &c., and said he thought
we might find some late specimens, but that the bulk of it was over, the proper
flowering time being May or June, and not July and August, as stated in most
botanical works, and that this year was an earlier one than usual, owing to
the small amount of snow which had fallen in the winter. He advised us to
try the Watschiger Alp, and not the Kuhweger, though the latter is easiest to
get at. So we settled to start at 5 the next morning, driving as far as possible,
and engaged Josef Gobendorfer as guide.
July 26. A perfect summer’s day. At 5.10 we were off in an einspanner,
and in about three-quarters of an hour arrived at the village of Watschig.
Here we alighted, and, crossing the Gail by a wooden bridge, found ourselves
in shady pinewoods, which we traversed for a mile or so till we came toa
brawling stream, where the ascent soon began in earnest. We had to mount
along the bed of this stream, crossing it many times. Then up a very steep and
rocky mule track till we came to a small lake with wonderfully transparent
water (the Watschigersee). It was full of pine trunks. Then up again till we
came in sight of the chalets on the Alps, and our guide pointed out to us
the first plants of the Wu/fenza, but, alas! utterly over. We began to doubt
whether we should find any flower at all. However, we found some other
plants quite new to us and very pretty, especially one white flower of the order
Caryophyllee. Waving rested awhile, we mounted yet higher up the slopes
of the Gartnerkofel, and now we came upon the Wz/fenza in extraordinary
abundance, covering in places every atom of the ground, young plants growing
almost on the top of old ones, and seeming to struggle with them for
existence ; but nearly all were out of flower, the tall seed-spikes rising in every
direction, and showing what a splendid display there must have been earlier in
the year. Our guide told us the whole mountain side here appeared dark blue ;
but higher up than this (we were about 6,000 feet) the plant is entirely absent.
The whole appearance of the Alp is like one vast garden ; lower down, where
the Wzuifenia does not occur, there are great beds of Alpine roses, and by the
stream many saxifrages and other flowers. It is appropriately called ‘¢‘ The
Garden Mountain.” The Alpine roses were in places covered with curious |
galls, looking like small peaches, and some bright scarlet, like tomatoes, of
great size. To return to the Wu/fenza—after a long search we found about a
dozen specimens, some of them with flowers still perfect, and some good enough
for a sketch in our a7. Hist. Journal.
Waulfenza may be thus characterized.
A glabrous herb, with perennial stalk. Leaves nearly
all radical, stalked, crenulate. Flowers in a one-sided cyme,
blue, calyx 5-partite, sepals narrow. Corolla with cylin-
drical tube, narrowed. Lobes four, the upper bifid, the lower
ones either undivided or crenate. Stamens two, exserted ;
inserted between the upper lobes; anther cells divergent,
Wulfenia Carinthiaca. | 77
but confluent at the tips. Stigma capitate. Capsule acute,
septiferous ; scepes leafless.
Fl. end of May and June.
The species are as follow:
W. Carinthiaca, Jacq. Carinthian Alps.
W. orzentalzs, Boissier. Seleucia, N. Syria, (Aucher
Eloy), Antioch (Montbret.).
Cf. Boissier, F7. Orzentalis, IV.. pp. 430, 431.
W. Amherstzana, Bentham, Scroph. [nd., 46.
Western Himalaya,nr. Kumaon,and Afghanistan,
W.rentformis, Douglas ?
It is uncertain whether this belongs to the genus.
Wulfenta Carinthzaca, Jacquin (Mzscellanea 2, p. 62, t. 8).
Leaves oblong, crenated, somewhat narrowed at the base,
radical ; tube of the corolla swollen above the base, segments
of the limb rounded, upper bifid, lower crenate, lateral often
undivided, blue, whitish within: 1% to 2 ft.
Syn. :—Pedarota Wulfenia, Lamk.
Introduced to England, 1817.
Named by Jacquin in honour of the Rev. Francois
Xavier Wulfen, author of the Plante rariores Carinthtace.
The localities affected by Wulfenza are most circum-
scribed :
Nyman, Conspectus Flore Europea, p. 543, cites
“Carinthia meridionalis (Kiihweger Alp et secus Grise-
bachium in 1872 detecta a cl. Schenk in alia alpe huic
proxima) Carniola (Auernick Kofel el Ball 1865). Friul
(pr. Ponteba sec Pir. Syll.) alp.”
To which in the Supplement to the above, 1889, p. 235,
he adds:
“In Carinthia loca speciei natalia sunt (ex Pucher ; Gail-
thal, circa montem Gartner Kofel in Watschiger-Kihweger-,
Granitzer-, Zichel-, et Auernigalm: Hab. inter rupes; in
pascuis et silvaticis apertis, 1500-1900 metr. s.m.; loca italica,
78 Mr. JAMES COSMO MELVILL oz
ut in Conspectu indicantur, duo, sec. Caruel (1886) unum
solum sistunt ; Friul, et quidem in limite extremo bor.- or
alpium Italicarum in latere meridionali montis Auernick
Kogel, orientem versus a monte Nassfeld (1500 metr.) qui
versus boreali-occidentem a pago Pontebba (Pontafel) situs
est.”. Comment. 193.
In my Herbarium are specimens collected by Mr. Chas.
Packe from the ‘ Gartner Kofel, supra Hermagor Carinthiz,’
July 9, 1870. Alpen de Trdpolaz by Dr. Lagger. “ Vallich,
Carinthia, with no collector’s name, from the Boswell (Syme)
collection; and the specimens collected by Rev. A. E-
Melvill and Miss E. H. Melvill at the Gartner Kofel, July
27th, 1503.
These places, Gartner Kogel, Kiihweger Alp, Vallich
Trépolaz Alp, Granitzer Alp, Friul, Pontebba, are all within
a very appreciable distance of each other, say 10 square
miles, and may almost be called at most two localities, both
in the same neighbourhood. The Italian boundary line is
not far S. of Hermagor, and Friul and Pontebba are just
below it.
Bentham and Hooker, Genera Plantarum, Vol.I1., p. 913,
divide the large order Scrophularcnee into three series,
Pseudosolanea,
Antirrhinide,
Rhinanthidee,
these being again subdivided into twelve tribes. The tenth
in sequence, and the first of the series R/zxanthidea, is that
of the Digztalee, thus well characterized, the following being
a translation from the Latin :—
RHINANTHIDE. Leavesvarious. Inflorescence simply
centripetal. Lower lip or lateral lobes of the corolla
external in the bud. Stamens very rarely more than four,
often only two.
Tribus X. Digztalee.
Wulfenza Carinthiaca.
79
Corolla usually little if at all bilabiate, the lobes all plane,
at the apex and often confluent.
parasitic.
the lateral or one of them external. Anther-cells contiguous
Herbs, or shrubs, not
The following genera belong to this section :*
Stbthorpia, Linn. - -
Hemiphragma, Wallich -
Scoparia, L. - - -
Capraria, L. - -
Camptoloma, Bentham -
Digitalis, L. - - -
Lsoplexis, Lindley - -
Erinus,L. - - -
Campylanthus, Roth. -
Lafuentea, Lag. - -
Ourista, Comm, - -
Pucrorhiza, Royle - -
Synthyris, Bentham -
Waulfenia, Jacquin - -
| Calorhabdos, Bentham -
Fedarota, 1. - - -
Veronica, L. -
Aragoa,H.B.andK. -
6 sp
E Sp.
I Sp.
4 sp.
E Sp:
18 sp.
2 Sp.
1 Sp:
4 Sp.
LSp.
18 sp.
I Sp.
6 sp.
4 Sp.
Sle:
2 Sp.
circa 200 sp.
3 5P
W. Europe, Africa, India,
S. America.
Himalayas.
Tropics of both hemispheres.
W. Indies and S. America,
Mexico and Florida.
W. Africa.
Europe, Asia.
Madeira, Canary Isles.
Europe.
Canares, Cape de Verde,
and Arabia.
Spain.
N. Zealand, Andes of S. A.
Himalayas.
N. America.
Carinthia, W. Asia, Hima-
layas.
Himalayas, Japan, China.
Europe.
Europe, Asia, America, Aus-
tralia, N. Zealand.
5S. America.
This list of Durand’s entirely agrees with the arrange-
ment in Bentham and Hooker excepting in the removal of
the Chinese and Japanese genus of 2 species, Rehmannia,
Lib. and Fisch., to the Cyrtandreous section of the order
* Index Gen. Phanerogam, Durand, p. 296, being a revision to date (1889)
of Benth. and Hook. Gen. Plantarum, as approved by Sir J. D. Hooker.
+ Forbes and Hemsley in the Enumeration of Chinese Plants, Journ. Lin,
Soc., Vol. XXVI., p. 195, enumerate 5 sp, of Calorhabdos, but they allude to
the one celled ovary being more Gesneraceous than Scrophularious.
fe) Mr. JAMES COSMO MELVILL on
Gesneree, from which it had, with apparent reason, been
removed (Ge. Plant, I1., p. 960), as agreeing with Ourzsza
in several important details.
I have brought here to exhibit with the specimens of
Wulfenta from my herbarium, examples of all these genera
excepting two, viz.: Camptoloma, of which only one specimen
has ever been gathered, and Ca/orhabdos, which, as being so
near an ally of Wu/fenza, | am sorry to have been unable to
procure. As a substitute, however, I exhibit a plate of two
species of the genus.
We here in Lancashire can boast of, perhaps, the hand-
somest of the whole series, as it is the type, viz., Dzgztalzs
purpurea, to the Purple Foxglove, being one of the most
plentiful plants in the neighbourhood, often, as at Prestwich,
monopolizing everything else, self-sown, in a shrubbery, or
open space, and ornamenting many a woodside in the
summer. Many species of Veronica likewise abound
around us.
The genera have been placed with much care and
circumspection by the learned authors of Gen. Plantarum:
and there can be no doubt but that the nearest allies of
Wulfenia are
Ourisza, - - Stamens 4
Picrorhiza, - “ * 4
Synthyris, - - . 2
Calorhabdos, - : 2
and Pedarota, - - - 4
this last showing a decided link between this plant, and the
spicate Veronice (Pseudolystmachia, Bentham, Leptandra,
North), the first mostly natives of Europe and Asia, the
latter of North America.
Pedarota, Linn, in its’ two species P. Agevza, Te
and Sonarota, L., with the hybrid between the two,
named by Huter P. Churchillz in honour of Mr. G. C.
Waulfenia Carinthiaca. 81
Churchill, of Clifton, Bristol, the well-known European
botanist, shows much affinity, as already said, with Wudfenza,
especially in the species Boxarota, the flowers of which are
purple, while those of Agevza are yellow.
But the nearest approach to the genus in formation of its
corolla and other particulars is undoubtedly the N. American
genus Syuthyris,* Bentham. Here the flowers are small,
purplish for the most part, in a simple spike, the stamens
(two exserted) are situate close to the sinuses of the corolla,
which is 4 cleft, somewhat irregular. Style filiform, with
capitate stigma. The main difference between the two
genera is that the anther-cells are in Syuthyris not confluent.
Wulfenta is, however, a much more showy plant.
The genus Gymwnandra, Pallas, a small Oriental and
Arctic group, now placed in the WV. O. Selagznee, and allied
to Globularia, L., has several points in common both
with Pedarota, Synthyris, and Wulfenza,; indeed by George
Don, in Dichlamydeous Plants, Vol. 1V., p. 581, it was placed
in Scrophularinee, next to Wulfenza. Here the corolla is
bilabiate, upper lip either emarginate or bifid, lower one 2-4
cleft. Stamens 2. The order Selaginee has many points
in common with Scrophularinee ,; all (nearly) the species of
both orders turn black in drying, the Se/agznew are, how-
ever, as a ruleofa different habit; many assume an eriliform
appearance, and they differ mainly from the Scrophularinee
by the cells of the ovary being 1-2 ovulate, and even Ben-
tham and Hooker confess this character is not always to be
relied upon.
Lastly, the genus Ourzsza, Comm., native of New
Zealand, Tasmania, and the Andes of S. America, may be
compared with Wulfenia, as possessing many attributes in
* In May, 1872, I had the privilege of spendinga short time with the late Dr. Asa Gray, at
Cambridge, Mass., U.S.A., and, showing me Syuthyris Houghtoniana growing in the
Botanical Garden, he pointed out its characteristics and touched upon its afflnity to Wz-
Jenia, Digitalis, and Veronica, and, if I remember aright, mentioned that he considered the
genus one of the most interesting in North America.
82 Wulfenta Carinthiaca.
common, but the stamens are 4, and not exserted. The
habit of such species as the New Zealand O. macrophylla
would be, I should imagine, the same.
In a Flora like the European, in which are found very
large assemblages of certain genera like Wzeraczum,Centaurea,
Linaria Ranunculus, Saxifraga, and Carex, it is all the more
interesting to note a few isolated types which have just put
in an appearance, as it were, and only just impinge upon
the Flora.
How the Waulfenza first became established near
Hermagor we cannot divine, but it is evidently of Eastern
origin. The Dzoscorea, to which we have already alluded,
is even more interesting as being a member of a subtropical
genus, not otherwise known in Europe except in one
Pyrenean station, and the Ramondia Pyrenaica, Lam., with
its two allies Haberlea Rhodopensis, Frivaldsky, and /ankwa
fLeldreichiz, Boissier, of the natural order Cyrtandree, a section
of Gesneracee, otherwise tropical or subtropical, are parallel
instances of localization. These three are found, one in the
EK. Pyrenees only, the next in the Balkan Mountains, Thrace,
and the third, and rarest, on the Thessalian Olympus.
Other instances might be adduced: all one can do is to
note the facts, and attempt to draw conclusions. The
question of the geographical distribution of plants is most
fascinating, and some of the data are quite without the
possibility of solution. Our own islands afford plenty of
material; many of our rarest plants are confined to one spot,
and two, Sperantheus Romanzoffiana (gemmupara, Linn.) and
Evriocaulon septangulare, L., natives also of the Neartic
region, are unknown in Europe excepting in Ireland, and as
regards the latter the I. of Skye, in addition.
JACQUIN.
WULFENIA CARINTHIACA:
: of Plate I.
MEMOIRS AND PROCEEDINGS MANCHESTER LIT. AND PHIL. 800.
PROCEEDINGS. 83
| Wecroscopical and Natural History Section.|
Ordinary Meeting, December 18th, 1893.
Mr. R. E. CUNLIFFE, President of the Section, in the Chair.
Mr. J. F. ALLEN and Mr. J. WATSON were elected
Associates of the Section.
The PRESIDENT moved :—“ That the Section notes
with great regret the loss to science caused by the death of
ieeceevnadall, oD. M.D; DIC.L., Ph.D. F.R-S., F.C.”
Dr. BROADBENT gave a microscopical demonstration of
Infusoria found in water obtained from manure heaps.
Pee, MELVILL, F.L.S., exhibited a specimen of
Bulimus (Porphyrobaphe) labeo (Broderip) from Peru, a
very scarce land mollusk, conspicuous for the swollen,
almost diseased appearance of the marvellously incrassate
and reflected outer lip, which has deep pittings and crenula-
tions all over its swollen and tumid surface, not dissimilar
to the appearance of cooled lava.
Mr. Melvill also exhibited eleven of the thirteen or
fourteen known Rhopalocera of New Zealand, which
country is the poorest in the world for its size for not only
these insects, but also those of most other orders, although
the bulk of the Coleoptera and Hymenoptera which do
occur are peculiar, and show the extreme antiquity of this
land, formerly, according to Wallace, a large continent
embracing the Macquaries, Lord Howe Island, The Auckland
and Campbell Isles, and Norfolk Island. That it has been
dissociated from Australia from the earliest times, is evident
by the differences in the Flora as well as in the Fauna.
84 PROCEEDINGS.
“The Butterflies” remarked Mr. Melvill, “are as
follow :
DANAIDA.
Hlamadryas Zotlus (Fabr.).
Also occurs in Australia.
Danais Evrippus (Cramer).
A North American species, very nearly cosmopolitan.
NYMPHALID~.
Pyramets [tea (Fabr.).
Also in Australia.
P. Gonerilla (Fabr.).
Endemic.
A handsome species.
P. Carduz (1).
Quite cosmopolitan. Known in England as the
‘Painted Lady.
ing the boundaries of human knowledge in the future as it
has been in the past.”
In answer to one of the members, Mr. WILDE said that
the electricity from the Corporation mains could be rendered
suitable by means of an induction coil for the ozonizing of
oxygen for bleaching purposes.
Special interest was manifested by the members in
Mr. Wilde’s exhibition of a new line which he has observed
in the spectrum of thallium, and in experiments with
his “Magnetarium,” to illustrate his theory of terrestrial
magnetism.
98 PROCEEDINGS.
Ordinary Meeting, February 6th, 1894.
Professor ARTHUR SCHUSTER, PH.D., F.R.S., Foie
President, in the Chair.
The thanks of the members were voted to the donors of
the books upon the table.
Mr. RoBERT MOND, M.A., F.C-S., of Winnington Hall,
near Northwich, was elected an ordinary member of the
Society.
Messrs. H. GRIMSHAW and R. E. CUNLIFFE were
appointed auditors of the accounts for the current year.
Professor SMITHELLS, of the Yorkshire College, read a
paper on “Flame and Flame Spectra,” and showed a series
of experiments. After separating the inner and outer cones
of a coal gas flame, he showed that lithium burnt in the
inner cone and copper oxide or chloride in the outer cone.
The paper contributed considerably to the question of the
temperature of flame and the causes of its luminosity.
Professor DIxon, Dr. BAILEY, Dr. BOTTOMLEY, Dit
HARTOG, Mr. JONES, and Dr. SCHUSTER Joined in a long
discussion on the interpretations of Professor SMITHELL’S
experiments.
PROCEEDINGS. 99
[Wecroscopical and Natural History Sectzon.]|
Ordinary Meeting, February 12th, 1894.
Mr. R. E. CUNLIFFE, President of the Section, in the Chair.
Mr. ROGERS exhibited specimens of Egyptian cloth
from the Fayoum, twelve hundred years old.
Mr. BAILEY drew attention to the weaving and the
pattern, and suggested that it could only have been pro-
duced by means of a loom constructed on the Jacquard
principle.
Mr. ROGERS also exhibited specimens of cotton silicate.
Dr. BROADBENT exhibited large specimens of cloth
prepared from the bark of trees, decorated with geometric
coloured patterns by the natives of the Samoa islands.
Mr. HYDE exhibited several cockroaches found near the
Ship Canal at Ellesmere Port, supposed to have been
conveyed from the United States in cargo.
es SS
100 PROCEEDINGS.
Ordinary Meeting, February 20th, 1894.
Professor ARTHUR .SCHUSTER, Ph.D., F.R-S, Faas
President, in the Chair.
The thanks of the members were voted to the donors of
the books upon the table.
Mr. W. E. HOYLE, M.A., exhibited the following shells,
recently acquired by the Manchester Museum :—
(1) Bathybembix argenteonztens,from Japan. A character-
istic deep-sea form, with delicate sculpture and pale irides-
cent colouration.
(2) Columbarium pagoda. A rare marine shell from
Japan.
(3) Columbarium distaphanotis. A beautiful shell, of
which the type-specimen from an unknown locality is unique.
This example is from the Cholmondeley collection.
(4) Opzsthostoma mtrabile. A land shell from Borneo,
in which, after a certain number of spiral turns, the shell
bends upwards and the mouth comes to lie close to the
apex.
(5) Palaina Quadrasz, An exquisitely sculptured oper-
culate land shell from Manila, in which the first whorls form
a right-handed and the last a left-handed spiral.
Professor SCHUSTER exhibited an apparatus in use at
Owens College for testing clinical thermometers, and read
the following note :—
“The Owens College has, during the last few years,
undertaken the testing of clinical thermometers for medical
men and others. It is the object of this note to describe the
apparatus by means of which a number of these thermo-
PROCEEDINGS. IOI
meters can be conveniently tested at the same time. The
apparatus consists essentially of two cylindrical vessels, one
being placed inside the other. Both are filled with water.
The thermometers are placed in a carrier inside the inner
vessel. The water in the outer vessel is maintained at any
desired temperature by an electric current passing through
a platinum wire in the water. The water in the inner vessel
is kept stirred by means of a revolving screw turned by an
electric motor.
“The details of the different parts are shewn in (Figs. I
to 3). Fig. 1 shews the carrier made of brass which holds
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the thermometers. They are all kept in place by an india-
rubber band pressing them against strips of brass bent so as
to form a triangular groove. Fig. 2 shews the inner
vessel round which a framework is fixed, carrying platinum
wire. This wire is insulated from the vessel by means of
indiarubber tubing which is placed over the brass supports.
Fig. 3 shews the whole apparatus when put together.
The brass rod passing into the vessel carries a pulley at one
end and a stirrer at the other.
“The thermometers are compared at three temperatures,
Viz., 98°, 103°, 108°. The vessel, without the carrier, having
G
102 PROCEEDINGS.
been filled with water at some temperature below 98°, a
current is sent through the platinum wire of such strength
Pisce 2:
that the temperature ascends fairly rapidly to the required
temperature, this current strrength is then suddenly
reduced to an amount previously determined and chosen
so as to give a very slow and steady increase of temperature
in the inner vessel. This rise should not exceed o* IF. per
minute, but it is essential that the temperature should con-
tinuously rise during the time of testing. As soon as the
temperature has thus been regulated the carrier is plunged
into the water. There is at first a cooling of the water due
to the introduction of the carrier, but the rise in temperature
soon begins to reassert itself. The cooling may, if desired,
be almost reduced to nothing, by keeping the carrier before
insertion into the testing vessel in water of about go°, but
there is no particular object in thus complicating the
ne Ege
PROCEEDINGS. 103
method of procedure. The thermometers are kept in the
water for a sufficient time to allow them to acquire its
temperature. The standards are then read off, the carrier
fem out, and the thermometers may be read off
aecicure: che operation is repeated’ at the other
temperatures for which the testing is to be carried out. As
the ultimate standard of temperature, I use at the College
a thermometer calibrated carefully at the Bureau Interna-
tional des Poids et Mesures at Paris. With proper precau-
tions a temperature can be read off to three or four
thousandth of a degree Centigrade. The College also
possesses a thermometer divided into tenths of a degree
Centigrade, compared with the Standards of the Technische
Reichs Anstalt at Berlin. Both thermometers agree in their
indications; they are made of glass, the composition of
which in each case is definitely known, and their indications
may without trouble be reduced to the air thermometer if
desired.
“T have, further, two thermometers compared at Kew.
One of them (A) is divided into fifths of a degree Fahren-
heit, and ranges from goto 115. Unfortunately it does not
contain the freezing point, so that its changes cannot be
followed. The other (B) is divided into tenths of degrees,
and ranges from 90 to I10. Another part of the stem,
separated from the rest by a bulb, is divided from 30° to
30°, so that its freezing point may be tested at any time.
Finally, three clinical thermometers are also used for com-
parison, two of them having been standardised at Berlin
and one at Kew.
“There is some doubt as to what the scale of temperature
used at Kew really is; but the difference between the Kew
temperatures, and the scale used on the continent, being
probably about =4th Fahrenheit near 100° F., is of no im-
portance as regards clinical thermometers.
“The following comparison shows the agreement between
104 PROCEEDINGS.
the different thermometers used as intermediate standards in
an experiment carried on exactly as in an actual test :—
Kew, B reading, 101°4.
Clinical thermometer, found at Kew to be
COFFECE sie oor Sete Sti. oo!) Oa
(1) Clinical thermometer, found correct at
Berlin Mee ae oy ae +s) SOT
(2) Clinical thermometer, taking account of
corrections supplied by the Technische
Reichs Anstalt ... i % i eR
“The thermometers agree, therefore, to the limits of
accuracy which can be attained.
“The College has tested about 300 thermometers in the
last two years, and, as a general rule, it may be said that
the corrections have been small; but it has occasionally
happened that thermometers were found to be wrong by
o'4 and 0°'5, which shows that no thermometer can be trusted
to be sufficiently accurate which has not been compared
with some standard.
“The result of testing also has shown that the more
expensive kinds of thermometers have errors as great as the
cheaper ones. The advantage which the more expensive
thermometers claim, of being more rapid in their indications
is often illusory. When a clinical thermometer is plunged
into water of 100°F. it takes up the temperature almost
immediately, and as to the time required when the ther-
mometer is placed into the mouth of the patient it is the bad
conductivity of the tissues of the mucous membrane which
causes the lag in the rise. The skin or tongue is, under
ordinary conditions, below the blood temperature, and is
further chilled by the introduction of the cold thermometer.
By reducing the mass of the thermometer the first chilling
effect may be diminished and the instrument would indicate
more quickly the correct blood temperature. But the gain
is not as great as is generally supposed.”
PROCEEDINGS. 105
Mr. THOMAS Hick, B.A., B.Sc., read a paper “On the
primary structure of the stem of Calamites.”
A discussion ensued, in which Professor WEISS and
Mr. CHARLES BAILEY took part, the latter commenting on
the rapid advances which are being made in the knowledge
of fossil botany, which threaten, in his opinion, to make it
necessary to revise all the classificatory work which has
previously been done.
General Meeting, March 6th, 1894.
Pretessor ARTHUR SCHUSTER, PH.D., F.R.S., F.R.A.S.,
President, in the Chair.
Professor A. S. DELEPINE and Dr. G. H. BROADBENT
were elected ordinary members of the Society.
Ordinary Meeting, March 6th, 1894.
Proiessor ARTHUR SCHUSTER, Ph.D., F.R.S., F.R.A.S.,
President in the Chair.
The thanks of the members were voted to the donors of
the books upon the table.
Reference was made to a recent display of Aurora
Borealis visible in Manchester.
Mr. W. E. Hove, M.A., gave a demonstration of the
luminous organs of cuttle fish, exhibiting sections with the
aid of the lantern and under the microscope.
A conversation on the causes and purposes of apparent
self-luminosity in the eyes of carnivorous animals ensued.
es
106 PROCEEDINGS.
Ordinary Meeting, March 2oth, 1894.
EDWARD SCHUNCK, PH.D., F.R.S., F.C.S., Vice-President,
in the Chair.
The thanks of the members were voted to the donors of
the books upon the table.
A discussion on meteorites took place.
Mr. JULIUS FRITH read a paper “On an analysis of the
Electro- Motive Force and Current Curves of a Wilde
alternator under various conditions.” The object of the ex-
periments described was to determine how far the behaviour
of an alternator containing iron in the armature agrees with
that of the theoretical alternator without iron. It was
stated, as an approximate result, that the agreement was
fairly good.
[Wicroscopzcal and Natural Hestory Section.|
Ordinary Meeting. March 12th, 1894.
Mr. CHARLES BAILEY, F.L.S., in the Chair.
Professor F. E. WEISS, of Owens College, was elected a
member of the section.
Mr. HYDE drew the attention of members to the flowers
of the alder, poplar, willow, hazel, and birch, which are
unusually large, numerous, and early this year.
Mr. ALLEN exhibited specimens of natural asbestos,
and of silicate wool, produced by steam blown through slag
when in a molten condition.
Mr. BROADBENT exhibited additional specimens of
genatoo (tapa,) prepared from the bark tissue of trees by the
natives of the Samoa Islands.
r
PROCEEDINGS. 107
Ordinary Meeting, April 3rd, 1894.
Professor ARTHUR SCHUSTER, Ph.D., F.R.S., F.R.AS.,
President, in the Chair.
The thanks of the members were voted to the donors of
the books upon the table.
Professor OSBORNE REYNOLDS read the following note
“On the Aurora Seen at Fallowfield on March 30th, 1894.”
“ At 10.20 p.m. on March the 30th I observed, from the
Ladybarn Road, immediately in front of my house, which
runs east and west, that there was an unusual amount of
light, for the time of year, all over the sky on the northern
side of the zenith, from east to west. At first it was only
the amount of diffused light on the northern side, as com-
pared with the southern, that caught my attention. The
sky was perfectly clear at the time, and the stars were
bright over the south, while over the north only the larger
stars were visible. There was no moon.
“Tt soon became evident to me that the light was
that of the aurora; but at first it was only remark-
able for the amount of diffused light, of a pale green
for the most part, but passing into red towards
the south. After observing it for some 15 minutes
aie appearance became much more remarkable
Streamers rose towards the zenith from all parts of the
northern horizon with great rapidity and vanished again
as quickly, and following these up to the zenith I saw what
I have never seen before. The sky was in a state of
fluttering light, wave following wave three or four a second,
the waves moving in the direction of the streaks of light
which suggested showers of luminous hail. The most
remarkable thing was, however, that the appearance of
108 PROCEEDINGS.
waves was owing to the fluctuation of light in set places—
more or less a series of broad bands across the direction of
motion of the waves. These broad bands of misty
white, fluctuating light, with more or less well defined
dark between, preserved a set shape. The light ap-
parently ended in a very bright arc like “ay ‘one
bright cloud running in an irregular line east and west
through the zenith. The line had a decided wriggle in it
near the zenith, and on the north was a dark space with
another bright band with a corresponding wriggle, so as to
create the appearance of a dark river between two bright
banks. This shape lasted some time, disappearing and
reappearing with the light. Watching this phenomenon,
and looking towards the zenith, it became clear that the
waves of light were moving nearly vertically, a little
towards the south, and that they only took effect over a
portion ofthe sky. Thus the motion seemed to diminish
as it neared the zenith, and in the bright arc, exactly as
though there was an illuminated vertical hail storm. I
watched it about half-an-hour, when the zenith effects
seemed to me to be diminishing.”
Mr. GWYTHER gave an account of the appearance of
the phenomenon at Buttermere, where it presented a some-
what different aspect. Mr. BROTHERS and Professor
SCHUSTER also took part in the discussion.
Mr. HENRY WILDE, F.R:S., read a paper “Onpeme
Influence of the Configuration and Direction of Coast Lines
upon the Rate and Range of the Secular Magnetic
Declination.”
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MEMOIRS AND PROCEEDINGS, MANCHESTER LIT. AND PHIL. SOC.
The K-partitions of the R-gon. 109
On the k-partitions of the R-gon. By the Rev. Thos.
P. Kirkman, M.A., F.R.S.
(Recezved, October 17th, 1893.)
A tape-face in a partitioned R-gon is either a triangle
having only one edge, or a quadrilateral having two opposite
edges, in the contour of the R-gon. No tape-face carries a
marginal triangle.
The first step in the reduction of the general k-par-
titioned R-gon is to drop out all its tape-faces.
The 14-gon, Fig. 9, has four tape-faces. By dropping
them out, we make it the 10-gon, Fig. 10, which has no
tape-face.
Fig. 9 has thus lost 4 contour edges, and 3 diagonals,
and therefore three faces.
The last operation in the construction of a definite
partitioned R-gon, is the insertion of the tape-faces that it
is intended to contain.
Our definitions and reasonings, until we come to handle
the tape, Fig. 8, apply to partitions in which there is no
tape-face.
Definitions: The bases of all marginal triangles of a
partition are marginal diagonals.
All other diagonals are non-marginal.
A prime partition is one whose diagonals are all marginal.
iies) 2. 5S, 2, 0, c, d, e, f, 6, 7, are primes.
A sub-marginal face has for an edge one, and only one,
non-marginal diagonal, and carries 251 marginal triangles.
A belt is a row of primes only, which have each more
than two marginal triangles, and cohere each with the next
by the united bases of two marginal triangles, that are
H
iG THE REv. THOS. P. KIRKMAN oz
hidden, being both creased under. J; is a belt of 5, Fig. 10
isa Delt of 2, primes.
We are to conceive two marginal triangles creased under
every non-marginal diagonal, in every partition.
When a belt falls asunder into its component primes,
the undercreased marginal triangles are seen in their right
position. Compare ABCiD,D: in 9§8,, with ABadbd out
‘ of JB, in the figures.
In 96:1, A and D2 are submarginal, but not in Figs. 1, 2,
3, 4) 5.
The belt JB, has 41 summits, besides the two terminals
crossed, and has 19 faces.
2. Every face of a partitioned R-gon, which has two
and only two non-marginal diagonals dd’ for edges, may be
and will be here considered, as a loose pane, and may fall
out with its complete contour and fringe of marginal
triangles, after which the two da’, whether they have or
not a common point, can become one; so that the number
of non-marginal diagonals in the R-gon is diminished by
one.
When a face has for edges 3+2 non-marginal diagonals
it cannot fall out, so that the 3+z non-marginal diagonals
can become one, diminishing thus by one the number of
non-marginal diagonalsin R. In Fig. His no face that can
drop out. IniJ8 any one of A BC: D, D, may so fall out ;
and any two, or all the five, can disappear with their mar-
ginal triangles. If all the primes that have for edges only
two non-marginal diagonals were so to fall out of Figs.
(1, 2, 3,4, 5), nothing would be left of all the five but exactly
our first figure H.
3. This H is zvreduczble, because it has no face, having
two, and only two, non-marginal diagonals for edges.
Definition: A k-partitioned R-gon in which is a face
that has for edges 3+z non-marginal diagonals, but no
The K-partztions of the R-gon. III
face having two, and only two, non-marginal diagonals, is
an irreducible partition. |
H has 23 summits and 14 diagonals, Its 15 faces are
9 marginal triangles, 4 sub-marginal faces, and 2 faces, a
triangle and a pentagon, each of which has for edges 3
-non-marginal diagonals that are the 5 dark edges of the
figure.
An irreducible H may have any number of faces that
have each for edges 3+2 non-marginal diagonals, z being
different or not in any two such faces; and such edges
will be called dark edges in H.
It is equally true that triangles and squares having two,and
two only, non-marginal diagonals for edges, and carrying no
marginal triangle, may fall out and leave only an irreducible
H. Thus, if in Fig. H the dark line 65 be completed into
either the triangle 655’ or the 4-gon 6'655’. carrying no
marginal triangle, either 655’ or ‘6655’ would have for edges
two non-marginal diagonals da’, and both could fall out,
leaving, after union of each @ and d@’, exactly the irreducible
H. We shall have to consider both the insertion and the
dropping out of such simple faces. They form, when out
of the R-gon, not a belt, but a tape, like Fig. 8.
The dark and dotted lines in Figs. (1, 2, 3, 4, 5), viz., the
pairs 65, 6'5’, 31, 3/1, &c., are the diagonals dd’ that could
unite if the primes between them were to fall out. The
dark line on the right in A, Fig. 1 is an error—it should be
not dark.
This brings out a novel and useful notion—that H can
be completed into a k-partitioned R-gon by simply splitting
its dark diagonals to receive one or more primes out of a
given belt. And it is evident to the reader that there lies
the secret of the construction upon H of Figs. (1, 2, 3, 4, 5).
4. If 4 be the number of the primes in the belt, and 4
the number of the dark diagonals of H, we have only to
form all the k-partitions of +, as a,, a,,... a,, Whose sum of
112 THE REv. THos. P. KIRKMAN oz
k parts is x, any number $0 of the parts beginning the
partition being zero (as ¢.g. a,=a,=a3=0, the rest being >o) ;
next, having named clearly our £ dark diagonals as 1%, 274,
374, ... £™, we have to insert into the 1** split diagonal, the
first a, ($0) of the x primes in the belt; next to insert into
the 2™¢ split diagonal the second number a, So of the
remaining +#—a, primes in the belt, and so on, lifting and
dropping the primes in their order till all the & dark diago-
nals have been, by the guidance of the same partition,
a,, 4,...a,, Charged each with a given number a, >0, of
primes, leaving none in the belt.
We have to make the like use of the next k-partition of
the number x to empty by its guidance the same full belt,
by charges >0 placed in every split diagonal, till every
k-partition has been so used to empty the same full belt.
If the number of the k-partitions of x so used is 7, we
shall have turned the same irreducible H into m different
partitioned R-gons. We shall presently see what number
m is, and be able to describe them. But our task is only
begun by this handling of all the 7 k-partitions of our
number x of primes in our belt, each in dictionary order.
We have to handle in the same way, for the charging of
our & dark diagonals of H, every permutation of the parts
of each of those 7 k-partitions, emptying our full belt into
the split diagonals M times; where M is the number of
all the permutations of the k-partitions of +; which M
includes the number 7 of the k-partitions above handled
unpermuted.
It is plain, that each of these M permutations bids us
distribute in a different way our x primes into our £-split
and unsplit dark diagonals, of which the z™ will be unsplit,
when the z™ place of the guiding permutation is zero. But
all this fuss of distribution is mere wind. M is all we really
want, and that theorem Q gives at once.
5. It is then evident that the number of distributions of
The K-partitions of the R-gon. 113
the z=5 primes of the belt JB: into the 2=5 split and
unsplit dark diagonals of H, is not less than M, that of all
the permutations of the 5-partitions of the number 5, zeros
and repetitions being allowed in the partitions.
By my theorem Q (vzde the coming volume of Reprint
of Educational Times), this number is the £ co-efficient
in (1+1)"""", ze, the 5 coefficient in (1+1)**’, which is
So7o0:;1234—120. This M=126 is all the answer we
can get if our +=5 primes can be exhibited in no other
belt besides one JB:. This can be the case only when the
primes are 5 squares in the belt, which out of it are 5 6-gons,
that are capable of only one order and posture in a belt JB,
having their marginal triangles all creased under and
forming not a belt, but a tape, like figure 8. Such primes,
having only two marginal triangles, are excluded by defini-
tion of a belt in Art, I.
There are many belts. There is no second 6-gon A,, nor
second 9g-gon Bz, having 3 marginal triangles ; but there are
three 14-gons (C) and three 15-gons (D) that all have
6 marginal triangles. These are the 2-zoned C, and the
monozones- C2 C;, Figs. a,c,¢; also the 3-zoned D,, the
asymmetric D. and the monozone Ds, Fig. 4,a,7
To secure the construction of all our partitioned R-gons»
these eight primes must all alike contribute to form a belt
of five, the belts so formed being equivalents.
6. We have to use the 18 equivalent belts following:
JB, ABCiD,D; ; 3B,, ABC,D.D; ; JB, ABCiDSD; ;
B:, ABC,D,.D; ; B:, ABC,D5Ds ; ‘Bs, ABG,D;Dy;
JB,, ABC;D:1D.; JBe, ABC,D.D,;; JB, ABC;D,D; ;
nine belts in which is no repeated prime ; and
JB, ABC,D,D,; JBi3, ABC: D2D2; YBic, ABCiD;D; 5
Bu, ABC,D,D, ; Bu, ABC,D2Dsz ; Bu, ABC,Ds3Ds 5
Bu, ABC3D,D; ; JBis, ABC;D2Dz ; JBis, ABC;D3Ds3 ;
nine in each of which is a repeated prime.
114 THE Rev. THos. P. KIRKMAN on
We have no z-ple: prime in our belt. The least 2-ple is
Fig 6; the least 3-ple is Fig 7. Observe that by z-ple we
mean always zoneless z-ple
If we had used a prime having 12 marginal triangles,
our belts, of += five primes each, would be numbered not by
half dozens, but probably by hundreds, all as much alike in
features as are the above 18 equivalents of one selected belt.
We shall speak in Art. 8 of the uw permutations of their
order in the belt of the #=5 primes, which are gure
different from the above M permutations of the parts of all
the # integral k-partitions of the mere number x The
numbers £ and # may differ in any way or degree. Here
4—=%5 is convenient:
Each of the 18 belts will add 39 of its 41 not crossed
(Art. 1) summits to the 23 of H (Art. 3); and 10 fagesyed
which 14 are marginal triangles, to the 15 faces of H.
At this point it is requisite that we clearly state the
complete problem that we intend to solve. It is this—to
enuinerate the number of partitioned R-gons, that all alike
fulfil the conditions following :—
ist. That they be all reducible to the same irreducible
H, or to an irreducible identical with H, in the names of
the polygons that compose H, two of which shall be exactly
the 3-gon and the 5-gon that have for edges the dark
diagonals in H.
2nd. That they each contain one of the 18 equivalent
belts above described.
3rd. That they all contain the same tape, Fig. 8.
Observe, that no partitioned R-gon can contain more
than one selected belt or tape, still less two irreducibles H.
Our problem resembles a famous old one: In how many
ways can you put all of f things into z fixed places, leaving
any tS of the z places vacant? In that, when e things are
wanted to put in places chosen, any e of the / things, if
they are all units, will serve as well as any other e of
The K-partitions of the R-gon. II5
the unplaced. But it is otherwise with our belt units. I
call them units because each has to contribute a unit to the
occupation of a place. To prevent confusion in our final
account, it is necessary, and fortunately it is sufficient, to
insist that if, directed by the first term of your guiding
permutation (any one of the above M), you begin by putting
(c) of my units in the place (the split diagonal) that you
have first chosen, you shall take the first cin the belt before
you; and that if you take @d more to put into your second
place, you shall take the next d in the belt ; and, moreover,
that my units in their new place shall sit in order, and wear
their marginal triangles, exactly as they did in the belt,
Mie diagonal split has a name, 12, 13, or ac; where
a1, having, out of a belt, # mar-
ginal triangles, can take in a belt, by using all its base-ties,
mu(m — 1 )2~* postures, and no more.
2. An 7z-ple prime, 72, having, out of a belt, 7 marginal
triangles, can take in a belt, by using all its base-ties,
27(7—1)z" postures, and no more.
3. An asymmetric prime that has, out of a belt, #z mar-
ginal triangles, can take in a belt, face-up and face-down,
21(# — 1) postures, and no more.
This gives us, if ~ be the posture-number of a prime,
and # the number of its marginal triangles,
For the 3-zoned A, m=3, 7=2;
2-zoned B, m= 3, m7—25
33
r 2-zoned Ci, m=6, 7=15;
3-zoned D,, #=6, t=10;
‘ t-zoned Ci, 7% =—6, 3 — 205
" 1-zoned C,, 7=6, 7=30;
1-zoned D,, 2=6, 7=30;
5 asymmetric De, m= 6, r= 60.
The table following gives the posture-factor of every
belt, as the product of five posture-numbers :—
a ai a et
The K-partitions of the R-gon. I2I
38.1, ABC, D, Dy JB, ABC, D, D,
2°2°15°10°60; II,= 36000 2°2°15°10°10; Iy=6,000
B., ABC, D, Dy | Bu, ABC, Di Di
2°2°30°10°60; Il,= 72000 2-220; 10: GOr tli £2,000
‘B:, AB Cs D, Dz Bu, AB C; Di D,
2;2°30'10°60; II; = 72000 22720, TOLEO + ka — 52,000
§B., ABC, D. D; JBis, AB C, Dz Dy
22°15°00°30; Il;— 108000 2°2°15°60°60 ; Il; = 216,000
§Bs, ABC; D: Ds JBu, ABC, D; Dz
212720°00:320; 1I;= 216000 22-20, 00100); lhe 4.22,000
JB:, AB C; D, D; JBis, ABC; Dz Dz
2°2°30°60°30; IIs = 216000 2°2°30°60°60; Ils = 432,000
B:, AB Cy D; D, Bic, AB Cy Ds; IDS
2°2°15°30°10; II;= 18000 2°2°15°30°30; Ilg=54,000
Bs, AB C, D; D, Bu, AB C, D, Ds
2°2520°30:10; Il, 20000 2°2°30°30°30 ; Ih710 = 8,000
Bo, AB (Fe D; D, Bis, AB C; D; D;
22:20;30;10; Il>— 26000 2°2520:20:20 ; lihg— 103,000
810,000 1,380,000
By our subsequent changes of postures in 126 times
distributed primes in the 120 times or 60 times permuted
belts, we multiply every posture-factor in this table either
by 126°120 or by 126°60.
It follows that the sum S of all the partitions of the
R-gon thus far constructed is
126°120°810000+ 126°60°1380000=S or S=22,680,000,000.
We need not distress ourselves about the undercreased
triangles in this hurly-burly of changing base-ties. The
pretty primes are nimble and well drilled. There is no fear
of damage to their wings in these thousands of millions of
evolutions.
12. In Fig. 4 and 5 are seen different postures of the five
distributed primes of the unpermuted ‘Bi.
In 4, D2 uses its base-tie 13 (Fig. Z); in 5 it uses 12 of
(7); the third triangle in (@) being hid in 4 and seen in 5,.
while the second triangle in (@) is seen in 4, but hid in 5.
122 THE REv. THos. P. KIRKMAN oz
In 4, D, uses its base-tie 14 of (6); in 5, °D, uses fen
(4). In 4, C, uses 52 of (2); in 5, C, uses 54 of (2), Tis
A and B have each made a revolution about its base-tie,
used in 4. B,in 5, should have a small marginal triangle
on the left at the fracture between 1 and I’.
The above S results would be nearly all that is required,
had we not to give an account of a third datum (Art. 6)
which is the tape, Fig. 8, of three triangles and three rect
angles that carry no marginal triangle.
All the S partitions above made have each (Art. 3) 33
diagonals, z2., places to receive, after splitting the proper
diagonals, the 6 units of the tape, which, after each distribu-
tion of them, will have added six faces to the 34 in each of
the S partitions.
Instead of 5, aByds, we have now 33 places to name, to
fix, and to split; in these we include the bases of the 23
marginal triangles in H, and in each of the 18 distributed
belts ; for by splitting such bases we cannot introduce a
new submarginal, as the tape carries no marginal triangle.
13. Our distribution of the tape can be exactly effected
in gIR, different ways, which is the number of ‘permuta-
tions of the 33-partitions of 6, without altering the order or
the posture of any prime in the tape. Such prime, out of
the tape, has two marginal triangles that in the tape are hid.
This 3IR, is by theorem Q, Art. 5, the 33'4, which is also
fae 7*~. COciicient Ol( 1-1) = =,1eu
38°37°30°35°34'33 = 2760681.
[-2°3'4°56
This is the partition-factor of the tape. Its permutation
and posture-factors are 20 and 8, so that we have 160 tapes
to distribute, which are all one (Art. 6).
The product of the three factors is
20°8'2760681 = 441708960= T.
The K-partitions of the R-gon. 123
Since each of these T variations of our distributed tape
will be combined with all the preceding S configurations,
without changing anything in the latter, we shall obtain
TS =441708960 X 22680000000,
= 1001795921 2800000000
different partitions of our R-gon. The (19+15)-partitioned
(39+23)-gon (Art. 3) has become by addition of the
6 faces and 9 summits of the tape, a 40-partitioned 71-gon,
and we have formed T.S of these asymmetrical propyramidal
71-gons, no one of which is either the repetition or the
reflected image of another. That is, if M be a million, we
have formed of them
10M?+ 17959M?2+ 212800M.
If the submarginals in H, standing on the dark edges 43
ana 21, be detached, the first is seen to be the prime.A, and
the second is a square under four marginal triangles; and
evidently neither of these could change the figure H by
undercreasing another triangle. The marginal diagonal of
that A should begin at 4.
The submarginals on the dark edges 65 and 31 are
monozones, each of which can, by undercreasing its other
two triangles, place its zonal trace in three positions, and
thus the two together can, still occupying 65 and 31, give
to H 3°3=9 configurations.
Further, these four submarginals can occupy the edges
43, 21,65, and 31 in 24 different ways, and by the same
changes of two concealed marginal triangles turn H into
24°90 = 216 ,equivalent H’s, all of which have been virtually
handled by us, and have each given us the same number
T.S of 40-partitioned 71-gons. Thus we have constructed
more than 2,000 millions of billions of them, namely,
-216.T.S =2163M*+ 879189M?+964800M.
124 THE .REv. THos. P. KIRKMAN oz
Each of them could be crowned upon its 23 marginal
triangles by a different asymmetric propyramidal 23-ace,
and the similar 216TS 23-aces could be by one entry
registered as a small fraction of all the asymmetrical pro-
pyramidal 23-aces, built by other belts on other irreducibles,
that are to be found among the asymmetric summits of the
72-acral 63-edra.
But since, in the solution of the problem of the Polyedra,
no asymmetric summits are obtained by coronation, none
of these 40-partitioned 71-gons are required in that solution.
All asymmetric summits, the a@-aces, d-aces, &c., are
given in that theory by their reciprocal a-gons, d-gons, &c.,
in the 63-acral 72-edra, which faces are obtained by their
edges, constructed in vast numbers by crowning (or imagin-
ing so crowned) penesolids with those edges. The only
asymmetric reticulations of use in the study of Polyedra
are quite elementary ones, by the zoned and zoneless
repetition of which round a circle are formed the sym-
metricals that alone are crowned, and give the z-zoned
and z-ple summits. Those small ones are readily obtained
by inspection of previous tables, in which they have been
again and again used.
This general problem of the k-partitions of the R-gon
is outside the theory of Polyedra. It may yet find its use
in analysis.
15. We have not above solved this general problem in
terms of & and R; that, I fear, is impossible. But it will
be seen that when with & and R are given the list of faces
in the irreducible H, with the number of its non-marginal
diagonals of which each is in a face that has more than one
other non-marginal diagonal among its edges, and when
the faces in R that have each two, and only two, non-mar-
ginal diagonals for edges are exactly given, whether they
carry or do not carry one or more marginal triangles, that
The K-partctions of the R-gon. 125
the problem is completely solved. And it is evident that
whatever be our data, as irreducible, as belt, and: as tape, it
is impossible that 2 of our constructions can be alike, unless
the primes are twice distributed in the same way, by the
guidance of the same permutation of the diagonals that
may be split to receive the primes. And this, fwzce, is
clearly impossible, because the number M of those permuta-
tions is exactly given by theorem Q, and none of them is
twice used ; vzde Art. 7.
It is impossible, also, that any one of our constructions
should be the reflected image in any position of another ;
because the reflected image of H has never been used.
If in a partitioned R-gon there is no irreducible H, the
R-gon is either a belt in which a tape is or is not distributed,
orit is a pair of collateral submarginals in which a tape is or
is not distributed, or it is a tape.
The tape in every case can be dropped out, and the belt
that remains can have all its possible configurations enumer-
ated by the above method, after which the tape can be
inserted again in every way possible.
Thus all the possible different k-partitions can be deter-
mined, both symmetric and asymmetric. But all the faces
must be exactly given in the sense in which the faces of our
18 belts were given in any single belt of them.
Hence it is quite correct (Art. 6) to say that no k-par-
titioned R-gon can have more than one irreducible H, one
belt, or one tape, although each of the three may have many
equivalents, due to permutation and altered posture of the
primes, and to the equal right, which like primes, CiC2C;.. . .
D,D,D,... (Art. 5) have to every possible admission into
the equivalent belts.
The number of distinct equivalent belts that we have
used in the pages preceding (Art. 11) is 9'120°x (h+Mk
+ .. +1])s)+9°60° x (Tio +Tit+ .. -+Tis); and these are all
given with any one of them that may be first handled
J
126 THE REv. THOS. P. KIRKMAN oz
and called JB. The number of equivalent tapes used is
1'20'°8 = 160,
16. There are yet questions about primes, belts, and
irreducibles that might be easily raised and disposed of in
reasonable limits; but they are forbidden ground. They
are too closely connected with the elementary theory of the
polyedra, upon the teaching and learning of which, over 30
years ago, was imposed, by the highest scientific tribunal, a
solemn and dire taboo. This is on record in p. 165,
Vol. CLII., 1862, of the PAzlosophical Transactions, in the
very last printed sentence of my complete Theory of the
Polyedra, thus: “Thus we have demonstrated, in this second
section, that the data of article xxxvi. are sufficient for the
entire completion of the tables A, B, C, D(xxxi.) faa
for faees and for summits. All that remains for the com-
plete solution of our problem, of classification and enumera-
tion of the P-edra Q-acra and of the P-acra Q-edra, is that
we show how these data can be obtained and registered,
without ambiguity or repetition. We shall consider first the
reciprocals of the faces (d) (f) xxxvi., and the edges (¢)
XK.
The taboo is the sudden, loud, and long silence of that
close.
My first two sections are very summary statements of
things to be distinguished and well-arranged in large groups»
before handling in detail, and not quite easy to a reader of
less than a De Morgan’s power. De Morgan read them
easily, and very early, without a complaint of my obscurity,
and, simply and only from the little just printed, so far shaped
to himself what was coming, that he could write the letter
now before me, dated “Adelaide Road, N.W., April 18,
1862,” expressing his satisfaction with it, with acute and
kind remarks on the success which he foresaw. But then, I
am here bound by candour to own that Professor De Morgan,
The K-partitions of the R-gon. 127
whom I never saw three times, was not of the Council, nor
even a Fellow, of the Royal Society.
That letter is the only evidence, direct or indirect, that
has yet reached me, that any competent judge, dead or
alive, ever tried to read six pages of mine on this. subject,
printed or in my MS.
Of my definite teaching ad zuztzo, to which a student at
the beginning would gladly turn, the first lessons are all in
my third section, which is evident in the above quotation.
Not a line of the third section was permitted to see the
light in 1862. And i have been informed by the Secretary
of the Royal Society that they have no intention to print
more of my JZemozr.
I have to confess that, a few years ago, I was tempted
to a violation—a very little violation—of this dread taboo.
Of that impiety I hope to die sufficiently penitent ; and I
am confident that I am much too virtuous to repeat the sin.
It is this—in Vol. XLIII., 1888-9, of the Proceedings of the
Literary and Philosophical Society of Liverpool, there is,
plentifully illustrated by plates containing 70 figures, an
analysis and synthesis of four autopolar solids, three that
have each six, and one that has nine, different edges.
Of this taboo, for my very brief time, I make no
complaint. My two first sections printed contain, not a
production—our planet is yet but young—but a sufficient
protection, of my theorems. And I am very far from denying
that what was done with them was perfectly regular and in
order, and simply what, when a like somewhat rare case
recurs, will with equal propriety be done again.
Wherefore I sing lustily, and shall sing to the end, the
song they have taught me—Procul este, profani! Floreat
Taboo!
It is a genuine and an effectual taboo. For it has a
droll side, which I leave to the reader who knows a little
about the Grand Prize Question that, early in 1858, was
128 THE REv. THos. P. KIRKMAN ox
published by the French Academy for their world com-
petition in 1861, was in 1862 kept open for another year,
and was apparently closed without result in 1864: wzde
Comptes Rendus, 1858, Vol. XLVI., p. 301; and 1862,
Vol) LV., p. ‘989.
There is often amusement in a contrast, and sometimes
in agreement. At the moment when the Academy were
recording, in that page (989), their decision to repeat, for a
fourth successive year, their offer to the circles of latitude
of their gold and honour for one who should work out
“en quelque point important la théorie géométrique des
polyedres,” that and every other important point of the
completed theory (completed before 1858) had, months
agone, been presented in London, and had there been flung
aside as a troublesome cumbrance, to be mentioned never
more for that generation. That was perfectly in order, and
has been as such accepted by all, for 33 years.
The reader will none the less enjoy what he finds of
droll in this taboo, if he has detected in that grave page
(989) a half-hidden twinkle or two of harmless fun.
It has also a serious side, that alone concerns me, in the
duty which'my reverence for the Royal Society lays on me,
of shunning in future all breach of their taboo.
The bold student, who in another lifetime or two may
have the valour to smash it, will see that my good fortune
in these k-partitions of the R-gon is due, first, to my
theorem Q, and next, to an old and very successful device.
In the Polyedra the diagonals under my propyramidal edges
and symmetrical summits were split for the insertion of tapes
of pyramidal bases, with vertices downwards, which were all,
by an easy routine of inspection of completed tables, after-
wards registered as higher and still higher metapyramidals,.
in groups ever larger and larger, each with its symmetry and
deletes to be read in one entry, soon enormous, without
ambiguity in class or number.
The K-partitions of the R-gon. 129
Of anything like a reason for the taboo I know nothing
fiatis not to be read in lines 4,5... of page 72 (the last
but three of the paper) of the Liverpool volume above
named.
Of my paper in that volume I can give a copy to the
mathematician who thinks it worth while to inform me of
his wish and intention to read it.
130 Dr. THOMAS EWAN ox
On the Osmotic Pressure of Solutions of finite Con-
centration. By Thomas Ewan, B.Sc., Ph.D., 1851
Exhibition Scholar in the Owens College.
(Recezved December 12th, 1893.)
In 1885, van’t Hoff* showed that the equation PV=RT>
which expresses the connection between the pressure, tem-
perature, and volume of a perfect gas, is also true for the
osmotic pressure of a solution. The behaviour of most
solutions is not in strict accord with this equation, and my
object in this note is to take into account certain factors
which are omitted in the simple equation PV=RT, and so
obtain an expression which shall approximate more nearly
to the truth.
The most important of these factors is the heat of dilu-
tion, as van’t Hoff pointed out. He says, after showing
that the equation PV=RT applies both to gases and
solutions :
“‘ Seulement la méme réserve nécessaire dans l’application en
“cas des corps gazeux convient encore ici, et l’analogie qu’offrent
‘ces deux états de la matiére est telle que l’origine de la restriction
“est. absolument la méme dans les deux cas. Aussitot que la
* concentration, soit dans les gaz soit dans les corps dissous, est
“telle que action mutuelle des particules n’est plus négligeable
‘on sait que dans le premier cas les deviations se font sentir et
‘de méme le raisonnement sur lequel se basent, pour la solution
‘‘les lois déduites ne peut plus étre accepté dans ces circonstances.
*¢ Ajoutons que pour les solutions, un phénoméne facile a produire
“‘trahit existence de l’action mutuelle des particules dissoutes ;
“ces actions donnent lieu 4 la production de traveaux intérieurs
** dans l’acte de dilution, qui se manifestent dans leur équivalent
* K. Svenska Vet: Ak: Handlingar 21. No. 17. 1885.
The Osmotic Pressure of Solutions. 131
“thermique ; par consequent les lois exposées s’appliquent a des
“solutions tellement diluées que la chaleur de dilution devient
*“‘négligeable.”
I have obtained the equations connecting osmotic
pressure, temperature, volume, and heat of dilution of a
solution, and on giving the value zero to the heat of dilution
the equations become identical with van’t Hoff’s.
Connection between Osmotic Pressure and Temperature.
The osmotic pressure of a solution cannot be directly
measured with any great accuracy, but it can be calculated
from the vapour pressure of the solution or from its freezing
point.
The relation between the osmotic pressure and the vapour
pressure of a solution was first given by van’t Hoff (loc.
cit.) and afterwards reproduced by other authors, first by
Gouy and Chaperon.* The form given by the latter is :—
Mee RTlog”2
+ Pp
)
BR:
where P= the osmotic pressure at T.
K is a coefficient which depends on the contraction which
takes place when the solution is diluted.
M, is the molecular weight of the solvent (as gas).
A, is the density of liquid solvent.
p, and # the vapour pressures of the solvent and solution
respectively, and
R the gas constant for 1 gram molecule.
The coefficient K is defined by Gouy and Chaperon+ by
the following equation :—
A being the density of the solution and zw the quantity of
* Ann. Chim. Phys. (6), XIII, p. 120. 1888.
+ Ann. Chim. Phys. (6) XII., p. 384. 1887.
132 Dr. THOMAS EWAN oz
solvent it contains to a given quantity of dissolved substance.
0
We may therefore consider K— as the increase of volume
ce)
which an infinitely large quantity of the solution would
experience if M, grams (=1 gr. molecule) of the solvent
were added to it. Call K caret and write the equation :
Po, = RTiog™ a
This equation is true for solutions of any concentration, and
is only subject to the restriction that the vapour of the
solvent over the solution may be considered as a perfect
gas.
The connection between the osmotic pressure and the
freezing point of a solution may be obtained as follows.
According to Kirchhoff’s}+ well-known equation connecting
the heat of dilution of a solution with its vapour pressure
we have:
dQ RT? d, p
se a ee! ee ] ye
dw JM, av © p
, : , l
where J is the mechanical equivalent of heat, and =
heat of dilution—is taken positive when heat is evolved on
—the
Ae dQ . ;
dilution. - is very nearly independent of temperature.
As a first approximation its variability may be neglected,
and the equation integrated gives
me
: Ww
The constant £ is of considerable importance, it is inde-
pendent of temperature, but varies with the concentration
of the solution. Its value may be obtained as follows :—
The heat required to melt 1gr. molecule of the solid solvent
at any temperature T (call it w,) is given by the expression
RT? dp
= cae l oO fl
I ate.
log =k+
Wr
t+ Ann. Phys. Chem. 103, p. 177. 1858.
The Osmotic Pressure of Solutions. 133
where 7, is the vapour pressure of the solid at T, and the
other letters have their former signification.
We also have
Wy = W, — (¢, — )(T, — T), ,
where w,=latent heat of fusion for I gr. mol. solvent at T,.
T,=melting point of solvent.
¢, and ¢,=capacity for heat for I gr. mol. liquid and solid
solvent respectively. Call. (¢,-4)=c and we get
RT? 4s, Dr
dT Sn, Da
Integrating this equation between the limits T, and T,
and remembring that at T,
W, +e(T,- T)=->-
P1i=Po
we get
ti Gud he T-T, loss)
Sar ont wr. oT
: ih :
after expanding log 7 and neglecting terms after the second
this becomes:
arte)... . ©
Now at the ale point of a solution its vapour pressure
is the same as that of the solid solvent at the same
temperature.
Call the freezing point of the solution F. At F, therefore,
2=hy and therefore
P1 De Po
—lo Al = log”) = loo—
ep, "71 °
At F, therefore, we have from equations (2) and (3), by
putting T=F and writing the quantities on the right hand
side of (2) equal to those on the right of (3) with negative
“sign, and after making all reductions,
b= a] omit aa -5("a* M, dQ t
TRE oe o(—F-) - F dw ean)
134 Dr. THOMAS EWAN ox
Substitute this value of £ in equation 2, and it becomes
a er ee
and finally equation (1), gives
which value substituted in 5 gives
—F cT/T,-F\?_. dQT-F
Pv, =J] wT tae g(a =) -¥ ae
In the following table the vapour pressures of some
copper chloride solutions calculated from their freezing
points, by means of equation (5), are compared with those
found. The determinations used were made by Mr.
Ormandy and myself.*
Concentration :
re To-F = (howisen) p. cal. p. found. Diff.
05 T°9Q05 "22 15086 15°033 "053
ala 4°12 78 14°788 | 14°706 082
"2 9°63 2.48 I4°I04 | 14'035 069
The differences are rather larger than the error in the
measurements of the vapour pressures, but may be due to
some extent to errors in the freezing points.
Equation (5) also shows that v. Babo’s law, according to
Po.
which Ae independent of temperature is only true when
d : : sa olncehi
= =0 ae will evidently decrease with rising temperature
when dy iS Positive, and vice versa. This conclusion has.
already been reached by Dieterici,} though in a different way,
* Chem. Soc. Fourn., 1892, p. 769.
+ Wied. Ann., 45, p. 207, 1892.
ee
The Osmotic Pressure of Solutions. 135
A number of interesting conclusions may be obtained
from equation 6.
(a) At the freezing point of a solution the external work
done when solvent is added to it ina reversible way is inde-
pendent of the nature of the dissolved substance, and it is
the same for all solutions in the same solvent which have
the same freezing point. The equation for the osmotic
work becomes at F—
ike oan 2
Fe ee ey
T F
This equation was first obtained by Arrhenius,* in 1892,
ina slightly different form, and in a different way.
(0) Again dividing equation 6 by T and bringing all the
terms which are independent of T together into one con-
stant, we get
Po, JM, dQ
7 = const + Wee re
It is easy to see from equations (1) and (2) that this may
also be written
dQ
oe eM ek (0)
Differentiating this with respect to T at constant volume
(or concentration )—
o(Pe) _ Rp
or
For any given solution v, may be regarded as indepen-
dent of temperature, and we get
(ae Rt _ Gonsiamibsty if tPA Pd hole Pex eet (8)
Vo
This result is quite analogous to the result obtained by
* Zein Ph, Chen. 103, p. 92; 1892.
136 Dr. THOMAS EWAN ox
Ramsay and Young,* that for a gas or liquid at constant
volume the pressure may be represented by an equation of
the form =4T —a where 6 and a are constants. From this
follows (a) =b= constant. The same result follows from
Van der Waals’ equation.
Equation 8 shows that the osmotic pressure may decrease
when the temperature rises, or (°") may be negative. The
sign of = is the same as that of 2, which depends chiefly,
as equation 4 shows, on the sign and magnitude of ae k
: dQ . :
will be — when = is +, and the sum of the terms contain-
dQ
ing ¢ and on in equation 4 is greater than the term con-
taining w,.
(c) If we put from equation 8
| bP
Rio ae in equation 7.
it becomes
(dP dQ
Pw, => TH oT), + JW ea
from which
oP\ P JM, dQ
(a i ee ae
This last equation becomes, when —=—=0.
es ae
roy APRS
That is at constant volume the osmotic pressure of a
solution is proportional to the absolute temperature when
the heat of dilution of the solution is zero. This result was
obtained by Van’t Hoff. (loc. czt. p. 11).
* Phil. Mag. (5) 23, 435, 1887.
The Osmotic Pressure of Solutions. 137
Connection between Osmotic Pressure and the Concentration
of the Solutzon.
_ The equations obtained so far are quite general, and
apply to solutions of any substance in any solvent, and show
how the freezing point, vapour pressure, heat of dilution
and osmotic pressure of a solution are connected among .
themselves and how they are affected by changes of tem-
perature. The effect of a change of concentration (that is
of the volume of solution which contains a gram molecule
of the dissolved substance) has not yet been considered.
Consider the simple case of a dissolved body consisting of
only one kind of molecules, the nature of which is not
affected by dilution. That is no dissociation of more
complex molecules into more simple ones, and no chemical
action is to take place on diluting the solution. In these
circumstances suppose the solution consists of z gr. mols. of
the solvent to I gr. mol. of the dissolved body. From
equation 7 we have
Pnv, = RTnk + J ie
dw
This equation is very similar to Van der Waals’ well-know
equation connecting pressure, temperature, and volume of a
gas or liquid.
To make this clear, consider a quantity of a solution (or
of a gas or vapour) in a cylinder which is closed by a
piston, the pressure on which just balances the osmotic
pressure of the solution (or the pressure of the gas). In
case of a solution the piston must be permeable for the
solvent, but not for the dissolved substance. The whole
arrangement is kept at temperature T.
Allow the piston to rise so that dw gram. of solvent is
dw
added to the solution, increasing its volume by K xR = UNG
e)
In the case of the gas let the volume simply increase by aV.
138 Dr. THOMAS EWAN oz
The osmotic pressure of the solution being P, and the pres-
sure of the gas f.
Then in both cases, in order to keep the temperature
constant, a certain amount of heat must be added, which is
the equivalent of the external and internal work done by
the solution (or oul in expanding. For the solution the
“JQ where dQ is the heat evolved on
adding dw er. on to the solution without doing external
work.
For the gas or vapour the work done is according to
Van der Waals pdV + [dV
The heat of dilution evidently represents the internal
work done in the expansion.
According to Van der Waals we have
a RT
Assuming that a similar equation is true for the sum of
external and internal work done when a solution expands,
we get
dw RT Kdw
ar qs or Ar?
‘Or
P(V.-8)- JE AV -B) = BE.
As R is the gas constant for 1 gr. mol. of substance, V
must be taken also as the volume in which a gram
‘mol. is contained.
Compare equation (10) with (9), viz. :—
dQ
Pav, — JZ Mn = RI nk |
nv, is the volume by which the solution diminishes when
n gr. mols. of solvent are withdrawn from it without changing
its concentration, it may, therefore, be regarded as the
The Osmotic Pressure of Solutions. 139
volume occupied in the solution by the solvent. V is the
volume of z gr. mols. solvent+1 gr. mol. dissolved body.
We have, accordingly,
V—-nv,=8,
where 0 is the volume in the solution of the dissolved
substance (for 1 gram molecule).
We get, therefore, (V — 4) =xv,
We have also =D a:
Lea Se
putting these values into equation (10), it becomes
Pn, —J Mn =f).
dw
By comparing this equation (which is obtained on the
assumption that an equation of the same form as that of
Van der Waals holds good for solutions) with (9), it is
evident that if the equation connecting osmotic pressure,
volume, and temperature of a solution is really of the same
form as Van der Waals’ equation, we must have
kn= +1.
The sign will depend on the sign of &.
The equation for the osmotic pressure of a solution
may, then, be written
P(V—8)=4RT+JnM,5° sia te ett)
The meaning of RT having the —- sign is, that when the
solution is diluted in a reversible way, the maximum of
external (osmotic) work being done, there is still heat
evolved by the system. This is a case which, so far as I
know, never occurs with gases.
The experimental material necessary to test the truth
: ies. f i
of the expression ogee is unfortunately not in existence.
The only substance for which I have been able to find
sufficient determinations of the freezing point and of the
14G Dr. THOMAS EWAN on
heat of dilution is alcohol, and even in this case the
determinations of the heat of dilution (Dupré and Page™*)
, d
are not sufficiently numerous to allow of the values of A:
being calculated with any approach to accuracy. The
following table contains, however, the numbers which I
have obtained. ‘The determinations of the freezing point
are Raoult’s.t
Grams alcohol F _k I iS
to 100 gr. H,O. highest. lowest. nN
15°19 20752 + '0065 += Oreg "0595
19°56 265°2 —°0765 —"O147 0765
24°70 2024 25a | 670454 "0967
29°15 260°2 or ye "0890 yee me bri
40°68 254'1 Tost "I241 "1591
Rr o2 248°7 "1985 "1545 "1996
59°66 244°8 "2405 "1365 "2335
7O'LS 240°9 ‘s5o6 "1788 ‘2744
I could find no interpolation formula which would
represent Dupre and Page’s numbers for the heat of
Q
solution of alcohol. I, therefore, calculated a from three
different curves. Owing to the small number of deter-
minations (there were only five which I could use) the
curves could not be drawn accurately, and, therefore, the
values of = obtained do not agree with each other. The
value of & has, therefore, been calculated by equation (4),
d
using the highest and lowest values of ~ found, and as will
Aa: Pe,
be seen the value of | lies between these limits, except for
the most dilute solution.
It may be remarked that in this case (viz., alcohol
dissolved in water) & has the negative sign.
* Phil. Trans., 1869, p. 501.
+ Ann. Chim. Phys. (5) 20, p. 220. 1880.
The Osmotic Pressure of Solutions. I4I
The equation (11) includes the equations which have
7 2 dQ_
already been given by Van’t Hoff for the case that 7 =o.
In this case it is easy to see from (4) that & is positive, and
therefore, equation (11) becomes
P(V —2)=RT.
If the solutions considered are dilute,—that is V large
compared with ,—this may be written—
Ev a
Again (11) may be written in the form
Pny,= {RT +I mo”
dw
or for
a = 0, this becomes - = 4
And from (1)
Po 7 p
iy ee
accordingly
Po _
°F =: ”
or for dilute solutions
PoP = i
Po nN
which is the well-known equation of Raoult. It was also
obtained in this form by Planck,* in 1887.
The expression for the molecular depression of the freez-
ing point of a solution follows from equation 4. Putting
ie Bt
DA Rae aon Yee
i We TO Pee doe
“M is called the molecular depression of the freezing point
of a solution, when ¢= the depression produced by g grams
* Wied. Ann. 32, p. 502. 1887.
142 The Osmotic Pressure of Solutions.
dissolved substance in 100 gr. solvent, and M = molecular
weight of the dissolved substance.
100 M Oe
We have accordingly = ye and writing
SS
, : i " Pa sci, Ss ‘7 Gy
MEMOIRS ano PROCEEDINGS.
, , E 4
4 = 49 f a) “ 4 . ps
Oe ee are te ee ee) seals a 5 > : = _ ree - eee | - gh) bela ‘ ices aig _ ul apn ft ret tee eo OO SMe Seg ieee
LP eat
Wilde Ae y
4% Series Vol Vi
(Jtt4 bh) CLS, Ad ‘A
a aan oe
a Cen a pe
MEMOIRS ano PROCEEDINGS,
| OT PP ensayo PA |
| | Fat un ap YI202. SANLTED [ “$7124
MANCHESTER LIT ano PHIL. SOC. |
>
. 3
;
=a}
a a ; ;
= ee Sal (Eo PG e = eh . a - = = gem a *
ee Sa (oe - ae = ee ;
; sea : —— ~~ = ess c % Lee 4 ont) As
——— — — : : : 3 ; des
|i = re 23S se - a : 2 .
| - —_—— 3 = a
1 « = ( 2 : :
‘y - de an ey
NY
MANCHESTER LIT ann PHIL. SOC
a2 MEMOIRS Ano PROCEED/NCS,
Electro-Motive Force and Current Curves. I51
An Analysis of the Electro-Motive Force and Current
Curves of a Wilde Alternator, under various con-
ditions. By Julius Frith, Heginbottom Physical
Scholar of the Owens College. Communicated by
moet Schuster, Ph.D., F.R.S.
(Recezcved March 20th, 1894.)
These experiments were undertaken with a view to find-
ing out how far the actual behaviour of an alternating-
current dynamo follows the laws deduced for it from the
theory of the alternator ; and if the electro-motive force and
current deviate from the theoretical sine curve, how many
terms of the Fourier’s expression should be taken into
account. They have led to the conclusion that, for the case
of an alternator whose armature contains iron, at least
three terms of the Fourier’s expression must be considered,
—-
152 . MR. JULIUS FRITH on -
but most especially the third, the second being in most cases
comparatively small.
Description of Machine.—The Wilde alternator used con-
sists of two crowns of cast-iron facing each other; from
the internal surfaces of these crowns project the fixed field
coils, six in number, on each side. These are bobbins ot
wire wound on iron cores. The armature revolves between
these, and consists of six similar bobbins on tubular iron
cores, held ‘in position between two discs of brass which are
keyed on to the shaft. The six coils of the armature are
connected in series to the commutator.
Hig: 1.
D= Wilde alternator.
R= Resistance, without self-induction.
C= Ammeter.
E= Electrometer.
B= Two insulated brushes bearing on the ebonite disc which carries
the copper contact piece.
Principle of Intermittent Contact—On the end of the
shaft beyond the commutator is keyed an ebonite disc ; in
a slot cut in this, about ;; inch wide, a piece of copper is
fixed, and turned down flush with the ebonite. On this
disc bear two insulated brushes, side by side; it will be
seen that at one instant in every revolution these two
brushes are connected together, while remaining insulated
from the rest of the machine. . If one of these brushes
is connected to one pole of the dynamo, and wires are
Electro-Motive Force and Current Curves. 13
taken’ from the other brush and the other pole: of the
machine to an electrometer, the electrometer becomes
connected to the poles of the dynamo, at one definite point
in the revolution of the armature. This point is known,
and can be altered by the arm which carries the two insu-.
lated brushes moving round a fixed divided circle.
Method of obtaining Current Curves.—This arrangement
would give the E.M.F. curves at the terminals of the machine.
To obtain the current curves, the fact is made use of that
the current in a non-inductive resistance is in phase with,
and proportional to, the E.M.F. at the terminals of the
resistance. Therefore, if the electrometer can be connected
through the same intermittent contact apparatus to the
terminals of an ohmic resistance, the form of the current
curve can be obtained.
The Electrometer—The Electrometer feed was cena S|
quadrant, and consisted of an aluminium needle suspended
in the quadrant by a silver wire ; to the needle was attached
the mirror and a damping vane dipping into oil. Each
opposite pair of quadrants was connected to the ends of a
water battery of 48, 96, or 144 cells; the middle of the
battery was always connected to the frame of the instrument.
The wires from the intermittent contact apparatus were
connected respectively to the frame, and to the needle by
means of the silver wire suspension. |
With this arrangement of the electrometer, the deflection
is directly proportional to the difference of potential between
the needle and the frame. |
The constant of the instrument was mand by means of a
battery of Clark’s cells.
With 24 water cells 1 scale div.='87 valte
> 48 ” ” = A359
» f2 = ” ="29 5
Magnetization Curves of Field Magnets —To obtain the
magnetization curve of the iron of the field magnets, a flat
coil of 12 turns of wire was wound, and arranged so that it
154 Mr. JULIUS FRITH ox
could be suddenly withdrawn from between the field coils
and the armature, when the latter was at rest with its coils
in a line with the field coils. The ends of this coil were
connected to a ballistic galvanometer and the kick observed
for different values of the magnetizing current on suddenly
withdrawing the coil. Curve I. (Plate III.) represents the
results of these experiments.
E.M.F, Curves Varying Speed and Exciting Current.—
Curve II. (Plate IV.) shows the E.M.F. curves at the
terminals of the dynamo on open circuit, (1) keeping the
speed constant and varying the exciting current, and (2)
keeping the exciting current constant and varying the
speed of the dynamo.
Current Curves.—Curve III. (Plate V.) shows the effect of
taking current from the machine, the resistance coils through
which the current passed being nearly without self-induc-
tion ; the lag recorded being due to the self-induction of the
armature.
If E, the impressed E.M.F., be of the form
E,sinpé,
then in a circuit of self-induction L and resistance R the
current is given by
Tyee a
where sec Lp.
ana = R
From the observations shown in Plate V. the equations to
the curves are found by the method of least squares to be:
For the E.M.F. curve, R=co
= — 229sin(0 — 2°) — 16°4sin(26 — 3°) + 36sin(30 + 1°).
For R=21'5,
C= — 8:7sin(@ — 20°) — ‘14sin(20 + 84°) + °34sin(36 + 33°).
For R=9,
C= — 16-4sin(@ — 31°) — ‘4sin(26 — 61°) — r°6sin(30 + 51°)
For R=;
C= —20'7sin(0 — 64°) — *7sin(20 — 20°) — 1'9sin(36 + 12 ).
Electro-Motive Force and Current Curves. 155
The lag in the first term of last three curves is 22°, 34°,
and 66° respectively. From the formula
Tan 06=L#
R
where 0 = angle of lag
p=2rn
mu =alternations per second
L=self-induction
R =told resistance in circuit
the self-induction may be calculated as follows :—
tan22°= "4
“ L="4 x 21°93 _ ‘0174 secohms.
2°75
tan34 = °67
wou "67 x 943
2°6°75 ia F
tano6" = 2°25
jodi = 225.4 2°43. 116
27775 -
These show that the self-induction of the armature
decreased with the increase of magnetization of the iron in
the cores. This agrees with the results of measurements of
the self-induction carried on in the ordinary way with the
machine at rest. These give,
with the fields not excited,
L=:02 secohms ;
with the fields excited,
L=:013 secohms.
On taking power from the machine the irregularities
die out of the curve, and it becomes first nearly straight
from the maximum in one direction to the maximum in
the other, and then gradually approaches the sine curve.
Electrolyte.—Next a copper-plating bath, consisting of
two plates of copper 30cms. x 4ocms., placed Ioocms. apart
in an acid solution of copper sulphate, was put in circuit,
and a current of 10 amperes was passed through.
156 . Mr. JuLius FritH on
Se D : ae Oc
=e
iiig. 2.
I Intermittent contact. '
‘E Electrometer..
D Alternator.
B Copper bath.
C Ammeter.
R Resistance without self-induction.
A resistance of 4 ohms was placed in series with the
bath, and the curve taken at the terminals of the dynamo.
On Plate VI. are also drawn the curve for 10 amperes
passed through resistance, and the curve of the machine on
open circuit.
Next an arc lamp was substituted. for the copper bath.
The potential at the terminals of the lamp was kept
constant and equal to 40 volts.
Fig. 3.-
Electro-Motive Force and Current Curves. us 7)
The Electrometer can be alternatively connected to the
terminals of the lamp, for the E.M.F. curve, or to the
terminals of a resistance of 5 ohms for the current curves.
This is done by the key &.
The Lamp used was a simple hand regulating one, and
therefore had no series coils and no self-induction.
Two curves were taken at the poles of the alternator,
one with the lamp direct to the dynamo, the other with a
resistance of 1 ohm in series.
On the same sheet, the current and E.M.F. curves of
the lamp with 5 ohms in series are shown.
Fig. 4.
Blondil—lt is interesting to compare these curves with
some obtained by the French electrician Blondil—7he
Electrician, December 15, 1893. Some of these curves
almost exactly agree with the ones drawn on Plate VII.
Surging of Lines——Plate VIII. shows the surging of the
lines of force of the field magnets. This was measured by
fitting over one of the field coils a light wooden frame which
carried 155 wires stretched radially across the face of the
pole, in the air gap between the fields and the armature.
The surging of the lines past these induced in them an
E.M.F., which was measured in the usual way by the electro-
meter through the intermittent contact apparatus. The
induced _E.M.F. is proportional to the rate of motion of
the magnetic field. This motion must in a large degree
account for the deviation of the electro-motive force
and current curves from simple sine curves,
L
158 Mr. THOMAS HICK on
ve the primary structure of The Stem of Calamites.
By Thomas Hick, B.A., B.Sc., Assistant Lecturer
in Botany, Owens betece Manchester. Communi-
cated by F. E. Weiss, B.Sc., Professor of Botany
in the Owens College. ,
(Received February 20th, 1894.)
Though a great deal has been written on the anatomy
of the Stem of Calamztes, the references in the literature to
its primary structure, that is, the structure previous to the
commencement of secondary thickening, are extremely few.
Binney, who was struck with the fact that the size of the
specimens met with varies within wide limits, refers! to
small stems which were not more than 3/50 of an inch in
diameter, but even in these secondary thickening had
begun, for his description shows that a zone of secondary
xylem, at least two elements in thickness, had already been
developed. Solms-Laubach remarks that “almost all the
petrified specimens which have been examined show the
presence of secondary wood,” and gives no description of
the stage where such wood is absent; while Schenk?
candidly confesses that in all the sections seen by him the
formation of secondary wood had already begun. It is only
in Williamson’s fine series of JZemozrs that any account of
the early condition of a Calamitean stem is to be found, and
this is given in the ninth J/emozr, which was published in
1878.
In that MZemozr* Williamson describes several stems
which were still in an early stage of development, but in
1 Observations on The Structure of Fossil Plants, Part I., p. 16. Lalaeon-
tographical Society, 1868.
2 Fossil Botany, p. 295.
3 Die fosstlen Phlanzenreste, p. 107.
4 Philosophical Transactions, 1878, p. 322.
The Primary Structure of the Stem of Calamites. 159
all of which the pith, carinal canals, and cortex were
distinguishable. One of them was “not more than 0'033
inch in diameter,” and the stage it had reached may be
inferred from the following description which Williamson
gives of it :—
“The medullary cells are here unruptured, the medullary
fistular cavity having as yet no existence. Nine longitudinal
internodal canals are seen, and these form the only recognisable
line of demarcation between the pith and the bark [cortex]. There
is little difference between the cells of these two structures.” ?
Another, which was slightly more advanced, he describes
thus :—
“We still discover the bark [cortex], the internodal canals,
again nine in number, and the medullary parenchyma; but the
bark [cortex] in this example is a thick layer of parenchyma of
coarser tissue than that composing the medulla, and the latter now
displays a central fissure, which obviously indicates the commence-
ment of the medullary fistular cavity. We have but still very slight
indications of the formation of woody wedges external to each or
the internodal canals.” ”
From these descriptions and the figures which accom-
pany them, these two stems seem to have been so young
that even the primary structure had not received its full
development. Summarising the facts obtained from a study
of the whole of the specimens Williamson describes this
early condition and some of the subsequent changes in the
following terms :—
“One thing is clear, viz., that the bark [cortex] as we see it in
Figs. 8, 10 and 13, is a primitive generalised parenchyma ; but as
the stems become arborescent this generalised tissue developed
within its interior the thick layer of prosenchyma, which resembles
so closely the cork layer of living phanerogams.” ®
PTAC. Citas) Pa gees = 2btG.g Ds 322:
3 Jbid., p. 324. The figures referred to are on Plates 19 and 20 of the
Memoir. +: :
160 Mr. THOMAS HICK ox
Since the publication of this account of the primary
condition of the stem of Calamztes, I cannot discover that
anything has been added to it, a result which is doubtless
due to the fact that stems of a suitable age and in a proper
state of preservation are so rarely met with. In now
attempting to carry our knowledge somewhat in advance of
this, I shall base my statements upon an exquisite series of
sections prepared some time ago by Mr. James Binns, of
Halifax.
One of the specimens is a transverse section of a young
stem, which is represented on Plate [X., Fig. 1. It is roughly
elliptical in shape, but broader at one end than the other.
The length of the major axis is +’; inch, and the breadth of
the broader end, at the margin of the pith cavity, is 5 inch.
Except the central part of the pith, which has disappeared,
all the tissues are preserved, and that in a degree of per-
fection and clearness which is rarely met with in the
petrifactions of Carboniferous plants. The peripheral part
of the pith forms a zone of parenchyma, a, on the inside of
the primary vascular bundles, which has a breadth of s$5
inch. If complete, the pith would form a nearly elliptical
mass of tissue, the longer diameter of which would be 34
inch and the shorter 335 inch. The periphery of the section
shows a number of irregular projections, which indicate that
the stem was not smooth but marked by longitudinal ridges
and bands. Some of them were merely narrow wing-like
extensions, 0, but others, c, were broader. The latter were
not rounded, however, but flattened, and had more or less
angular edges. How far accident has entered into the
formation of these ridges it is impossible to say, but the
normal appearance of the tissue beneath them proves that,
to a large extent, if not wholly, they are natural.
Surrounding the zone of pith are the primary vascular
bundles, @, Fig. 1, which are here 16 innumber, Like those
of Equtsetum, they are imperfect, the xylem consisting of
The Primary Structure of the Stem of Calamites. 161
little more than the carinal canal, formed by the breaking
down of the initial strand of vessels. A striking and
remarkable feature of some of these canals is the presence,
at the margin, of projecting elements, which I have no
hesitation in interpreting as the remnants of the vessels, v.
The presence of these elements gives the canals an
appearance which is perfectly identical with that of the
homologous canals of Eguzsetum, but the lateral xylem
elements found in the latter plant are not distinguishable.
External to each canal is a mass of small elements, Z,
which, from their position and their distinct character when
compared with the ground tissue on either hand and
between the canals, must be regarded as the phloem of the
primary bundles. It is true that some of the histological
characters of phloem cannot be recognised in these groups
of elements, but this is most probably due to the fact that
in the process of fossilisation, their contents have all
disappeared. If, however, they be compared with the
phloem of Lguzsetum after the protoplasm, &c., has been
removed, it will be found that they are in close agreement
therewith not only in position, but in the size and general
arrangement of the constituent elements. If a pericycle
ever existed outside this phloem, it is no longer recognisable.
Still moving outward, we next come to a sharply
defined line, s, which is traceable nearly all round the stem,
just outside the-ring of primary vascular bundles. The line
is slightly undulated, the parts opposite the bundles being
convex, and those opposite the medullary rays concave,
outwardly. I regard it as marking the boundary between
the stele, or vascular-bundle cylinder, and the cortex. In
most of my preparations, it is apparently a simple but thick
black “line,” but in the one under description, and one or
two others, there are vague indications of a single layer of
narrow cells in place of the “line” at some points. If this
could be proved to be the normal structure, few would
162 Mr. THOMAS HICK ox
hesitate to call the layer of narrow cells the endodermis,
and to regard the axis as monostelic. But at present this
has not been done. Nevertheless there are good reasons
for regarding this “line” as the boundary between the stele
and the cortex. In the first place, it is strongly suggested
by the typical species of Eguzsetum, eg., E. arvense and
E. maximum, which, it will be allowed, are something more
than analogous. In the second it is supported by the mode
of origin and the development of the secondary xylem, as
will be shown later.
Outside the “line” just dealt with, we have the cortical
tissues, which are here seen to present a considerable
amount of differentiation. At the first glance, indeed, it is
obvious that the cortex of this specimen has a remarkably
complex structure. It is made up of two layers or zones,
an outer and an inner, 9, z, between which runs a dividing
line, which is undulated and roughly parallel to the surface
‘of the stem.
The inner zone is the broader of the two—having a
breadth of 745 inch—and is generally much better preserved.
In the middle of it the elements, though of ‘different sizes,
are for the most part large and angular, and in shape and
arrangement are not unlike the xylem elements of the
vascular bundle of a fern. But the walls are not specially
thickened, and the cavities frequently contain black car-
bonaceous masses, #. Whether these represent special
substances, such as resin, tannin, or latex, or merely an
unusual accumulation of ordinary cell contents, it is
impossible to say. Between the black masses, which are
usually eccentric, and the distant cell wall, a faint concentric
line is often discernible, recalling the appearance of the
primordial utricle of recent plants. This, and the whole
appearance of the zone, seem to show that the contents of
these elements were introduced in the living state, and are
not mere infiltrations into empty cavities during the fossil-
The Primary Structure of the Stem of Calamites. 163
ising process. On the inner, and more especially on the
outer, side of these larger and more central elements, which
are practically continuous all round the stem, are smaller
elements of a different character, z. In transverse section,
they have a more circular outline, and there are distinct
evidences of thickening deposits having been laid down upon
the original walls. On the outer side of the zone under
description they form two or three layers, and at some
points they are found penetrating in triangular masses
between the larger elements of the middle. On the inner
side they chiefly fill up the angles between the larger middle
elements, so that the entire zone has a tolerably uniform
width, with more or less even and uniform margins.
The outer zone of the cortex, 0,is seldom well preserved,
but it appears to have been composed of a thin-walled
tissue, in which thicker-walled elements were imbedded.
The latter have very thick walls, with clear rounded lumina,
and are somewhat irregularly distributed. A curious point
is, that they vary much in size.
At the periphery of the section is the epidermis, but in
this, as in most specimens, its structure is for the most part
obliterated. At a few isolated points, however, we can
make out that it originally consisted of a single layer
of cells.
My efforts to obtain longitudinal sections of this type
of stem in its primary condition have not yet been as suc-
cessful as could be desired. Numerous fragments have
been met with, but no one large and complete enough to
give a connected view of the primary tissues in their longi-
tudinal aspect. Nevertheless, by putting together the items
of information picked up from a large number of these
fragments, we may obtain a fairly reliable idea of the
longitudinal structure, at least in its main outlines. The
following description is based upon knowledge obtained in
this way. | |
164 Mr. THOMAS HICK on
The pith, so far as it is preserved, is made up of thin-
walled cells, elongated longitudinally, which are usually
narrower at the periphery than towards the centre. In some
cases a few larger cells, with carbonaceous contents, are
intermingled with the smaller peripheral ones, but these are
not present in the transverse sections figured. They have
a close resemblance to the cells which occupy the middle of
the inner zone of the cortex. The pith cells at the nodes
are rounded, and may or may not contain accumulations of
carbonaceous matter.
The vascular elements which cling to the sides of the
carinal canals are not all of one kind. Some of them are
clearly annular, and others are spiral; but occasionally
reticulated ones are also present, a state of things which
may occur in Eguzsetum.
Longitudinal views of the phloem are much rarer and
still more fragmentary than those through the xylem, and
at present I can only say that the phloem elements apieer
to be narrow elongated structures.
Coming to the cortex, it may be said with some degree
of confidence that the larger elements of the inner zone,
though often considerably elongated, are nevertheless
cellular. They are, in fact, several times as long as broad,
they have oblique or square ends, and stand in vertical
rows. But there are no signs of thickening or sculpturing
of the walls. The carbonaceous contents are usually
retracted from the side walls, and at the ends sometimes
take the expanded, trumpet-like form, characteristic of
the contents of some sieve-tubes. This, and the arrangement
in vertical rows, suggests that they formed conducting
channels, but the nature of the conducted materials cannot
at present be determined.
With respect to the outer zone of the rita little has
been made out in the longitudinal view beyond the fact that
the thick-walled elements seem to be more or less fibrous
The Primary Structure of the Stem of Calamites. 165
in form, and probably belong to the category of scleren-
chymatous fibres.
From this account of the primary structure of this type
of Calamitean stem, it will be seen that the specimens now
described differ in many respects from those described and
figured by Williamson in 1878. As already stated, the
tissues are much more differentiated, and that in nearly
every part of the stem. In the pith, we have the elements
at the periphery smaller than those in the centre, and the
occasional occurrence of larger elements with black con-
tents, may be indicative of other differences. In the stele,
‘we have phloem strands accompanying the carinal canals,
to the walls of which the torn vessels still adhere, and there
is a sharp distinction between the stele and the cortical
tissues. The latter again are distinguishable into two
zones, and within each there are considerable histological
differences, which add to the complexity of the whole, and
make it a very different structure from the “primitive
generalised parenchyma” of Williamson’s specimens. My
own impression is, that these differences are due to the fact
that the latter appear to be in an earlier stage of develop-
ment than those under treatment, which seem to present
the primary structure fully matured and ready for the
initiation of secondary thickening. It is possible, however,
that the two sets of specimens do not belong to the same
type of Calamztes, and that this is the explanation of the
want of agreement between them. |
An interesting question in connection with the fossil
plants of the Coal Measures is the degree of correspondence
between the size of a stem and the extent of the develop-
ment.it has undergone. The preparations under considera-
tion appear to throw a little light upon it. The transverse
section of the stem which has been described in detail,
measures, as already. stated, 7; inch by sy inch. But my
collection includes others smaller than this, in which
166 Mr. THOMAS HICK on
practically the same structure obtains, and that in equal
perfection. Of these one measures +; inch by 35 inch, and
another, which is circular, has a diameter which is not more
than the latter figure. Thus in stems which range in dia
meter from =5 to 7s inch, we have the same differentiation
into stele and cortex, and within these an equal complexity
of structure.
Another subsidiary point of some interest receives fresh
elucidation from these specimens, viz., the nature of the
lacunae, which are almost constantly present in the primary
vascular bundles of Calamztes. Most palzobotanists now
accept the interpretation of Solms-Laubach that “in the
lacunae, or the tissue that fills them, we are dealing with the
tracheal initial strand of the primary bundle”! This
interpretation, however, has hitherto been based entirely
upon transverse sections, the author quoted pointing out,
that longitudinal sections bearing upon the point are
precarious, and “are of value only when the sculpture of the
walls is preserved, which is seldom the case.” No such
sections appear to have been described hitherto, and hence
it seems worth while to note that the sections here dealt
with are exactly of the kind required, and fully confirm the
interpretation of the lacunae suggested by Solms-Laubach.
These matters disposed of, we may now turn to one of
much greater importance, viz., the place of origin of the
secondary thickening and the first changes brought about
by the same.
Fig. 2 represents a stem of the same type of Calamites
as those previously described, but it is much older, and has
developed a zone of secondary xylem which is nearly 35
inch in breadth. It was partially described by Mr. W. Cash
and myself many years ago? and has its tissues much more
1 Fossil Botany, p. 298. ;
. Proceedings of the Yorkshire Geological and Polytechnic Society, 1883.
The Primary Structure of the Stent of Calamites. 167
complete and in a much finer state of preservation than
any other section I have yet come across. In it will be
seen the pith, a, surrounded by the carinal canals, d, seven-
teen in number, arranged as in the younger specimens.
But outside each carinal canal is a wedge-shaped mass of
secondary xylem, x, and between these masses are the
somewhat broad medullary rays,7. It will be noticed that,
as has been pointed out by several observers,’ the first
formed elements of the secondary xylem stand near or
abut upon the carinal canals, and the rest are developed
centrifugally in radiating rows. Hence, as the young stems
described in this paper show phloem strands in immediate
proximity to the canals,? it seems a warrantable inference
that the secondary thickening begins in the position usual
for open collateral bundles, ze., between the phloem and
the xylem. ?
As the development of the secondary xylem would
necessitate the displacement of the phloem and the ‘line’
of demarcation between the stele and the cortex, one
naturally looks for traces of these in the older stems; but
so far I have not been able to detect them. It is otherwise,
however, with the cortical tissues. At z we have the inner
cortical zone of the older stem, and it needs little examina-
tion to see that it is identical with that of the primary stem.
(Fig. 1, z.) The arrangement and general appearance of the
elements are the same in both cases, and the same may be
said of their histological structure. The breadth in the older
stem, as in the younger, is ;45 inch, so that there has been
no growth in the radial direction. Obviously, however,
there must have been growth in the tangential direction, as
the layer still completely encircles the stem, though not
quite so uninterruptedly as in the earlier stage.
1 See especially Binney /oc. cz#., and Williamson, Philosophical Trans., 1871.
* Ante, Pi
168 Mr. THOMAS HICK oz
In the outer cortical zone, we again recognise the thin-
walled tissue at 0, but its bulk is still small. In it area few
lacunae, Z, but whether they are natural air-canals, or due to
accidental rupture, there is nothing to show. The thick-
walled elements, on the other hand, have increased con-
siderably, and now form a dense thick hypodermal layer, s,
which appears to have been sclerenchymatous. The
elements of this layer are not arranged in radiating series,
nor are they grouped in triangular bundles, thus differing
from the corresponding tissues described by Williamson."
On the whole then, it would seem that the structure of
the cortex, as seen in the primary stem of this type of Ca/a-
mutes, retains its characteristic features for some time after
secondary thickening has set in, the chief modification, apart
from the doubtful lacunae, being the increase in the
mechanical tissue. | |
Reviewing the facts as set forth in what has gone
before, botanists will probably be most struck with the
remarkable features of the tissue which makes up the inner
zone of the cortex. From what I have seen of it, in many
preparations, I am convinced that it is an important tissue
both in a morphological and a physiological sense, though
I cannot as yet specify in what its importance consists. It
is not confined entirely to the stem, but is found also in the
leaves, where it forms a conspicuous layer, which extends
from one edge to the other, and runs from base to apex
beneath the epidermis on the convex side. Finally, an
identical layer is present in a similar position in the sterile
bracts of Calamostachys Binneyana, as 1 have shown else-
where,” awakening the suspicion that in the type of
Calamites here considered we have the plant that bore
Calamostachys Binneyana as its fruit-spike.
1 Phil. Trans., 1878, p. 3243; Lbzd, 1881, p. 465.
® Proceedings of the Yorkshire Geological and Polytechnic Soctety, 1893, p. 287-
The Primary Structure of the Stem of Calamites. 169
Not the least perplexing fact about this tissue is that it
appears to belong to the cortex, as has been pointed out in
the earlier portion of this communication. Insome respects
it is not unlike a well-developed phloem tissue, and when
the older stem was first described by Mr, Cash and myself
in 1884, we called attention to this, and tentatively suggested
that it might be the phloem of the secondary bundles.
Now however that we know it to be a constituent of the
cortex of the primary stem, and find it as a broad longi-
tudinal band in the leaves, it is clear that this view of its
nature can no longer be put forward. In 1876 M, Renault
described’ a form of Calamiztes, which he named Arthropztys
/ineata, in which he found a layer of cortical tissue in which
were elements that somewhat resembled those of the layer
before us, so far as one can judge in the absence of figures,
He speaks of it asa cellular layer, enclosing groups of resin
canals, placed in front of the secondary xylem bundles.
Solms-Laubach questions this interpretation,” but whether
true or not for Renault’s specimens, it is scarcely applicable
to the case before us, For here we have a zone of ézssue
which is practically uniform and continuous round the
whole stem, and not merely a number of isolated “ groups”
of elements, distinct from, but imbedded in, an ordinary
cellular layer. Moreover, the elements of this tissue are
themselves mainly cellular, and the carbonaceous masses
they contain are apparently derived from the normal cell
contents. They might be secretory reservoirs of some kind,
but their arrangement as a special tissue is not in favour of
this view, and their longitudinal course, both in the stem
and the leaves, is more suggestive of the function of con-
duction, as already stated.
Turning to Eguzsetum, as the living representative of
1 Comptes rendus, Vol. 83 (1876) p, 574.
2 Fossil Botany, p. 301, -
170. The Primary Structure of the Stem of Calamites.
Calamites, we find little in its structure to elucidate the
nature of the tissue under consideration. Strasburger
mentions’ that in LAguzsetum maximum tannin bearing
elements are scattered in the ground tissue, both of the
stele and the cortex, and that they are elongated structures
arranged in longitudinal series. These, however, are scarcely
comparable with the elements of the inner cortical zone of
Calamites, though they are not unlike the groups of cells
with black contents, sometimes seen in the pith.
For the present, then, we may leave the interpretation
of this peculiar tissue an open question, in the hope that
further specimens may soon be forthcoming to throw
additional light upon it.
EXPLANATION OF THE FIGURES.
fig. 1. Transverse section of the Stem of a young Ca/lamites.
Peripheral portion of the pith.
. Narrow and broad ridges respectively at the surface of
the stem.
@d. Carinal canals of primary vascular bundles.
v. Carinal canals with projecting vascular elements.
P
5
SSS
~
Phloem of primary vascular bundles.
Boundary between the stele and the cortex.
z, o. Inner and outer zones respectively of the cortex.
m. Elements of inner cortical zone with black contents.
m. Smaller elements of inner cortical zone.
Fig. 2. Transverse section of Stem of Calamztes with secondary
thickening.
i, Pith.
d@ Carinal canals of primary vascular bundles.
x. Secondary xylem. |
vy. Medullary rays.
z, 0. Inner and outer cortical zones respectively.
7. lLacunae in the outer cortical zone.
s. Sclerenchyma of do. do.
1 Histologische Bettrdge, Heft IIl., p. 433.
4 Series Vol W. Plate TK Catamites.
MEMOIRS AND PROCEEDINGS, MANCHESTER LIT.AND PHIL.SOC.
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PROCEEDINGS. 171
Annual General Meeting, April 17th, 1894.
Professor ARTHUR SCHUSTER, PH.D., F.R.S., F.R:A.S.,
President, in the Chair.
The following gentlemen were elected Honorary
Members :—
Eig eAun APPELL, Paris; J. W. L. GLAISHER;, D.Sc., F:R:S:,
Cambridge; Prof. L. KOn1IGSBERGER, Leipsic; Prof. M. Sopuus Lig,
Copenhagen ; Prof. A. Gouy, Paris; Prof. E. Warsur«, Freiburg ;
Dr. G. NEUMEvER, Director of the See Warte, Hamburg ; Prof.
Eee oToONne, F.R.S., Radcliffe Observer, Oxford ; Prof. H. A.
Row.tanp, For. Mem. R.S., Baltimore; OLIVER HEAVISIDE, F.R.S.,
Paignton, Devon; Prof. W. OstwaLp, Leipsic; A. G. VERNON
Harcourt, F.R.S., Oxford ; Dr. H. Desus, F.R.S., Cassel ; Prof.
T. E. THorps, F.R.S., London ; Prof. Prerrer, Jena; Dr. JoHN
Murray, Edinburgh ; Prof. Sir Wma. Turner, F.R.S., Edinburgh ;
Prof. A. WEISMANN, Freiburg ; Prof. SipNey Vings, F.R.S., Oxford ;
Prof H. M. Warp, F.R.S, Cooper’s Hill; Prof. C. M. GuLpBere,
Christiania; Pro. P. Waacer, Christiania; Prof. J. S. Burpon
SANDERSON, F.R.S., Oxford.
The Annual Report of the Council was presented and
.amended, and it was moved by Mr. J. B. MILLAR, M.E.,
seconded by Mr. S. C. Trapp, and resolved :—“ That
the Annual Report as amended be adopted, and printed in
the Society’s Memozrs and Proceedings.”
It was moved by Mr. W. E. HOYLE, M.A., seconded by
Mr. S. C. TRAPP, and resolved :—“ That the system of
electing Associates of the Sections be continued during the
ensuing session.”
The following gentlemen were elected Officers of the
Society and members of the Council for the ensuing year :—
President—HENRY WILDE, F.R.S.
Vice-Prestdents EDWARD SCHUNCK, Ph.D., F.R.S.,
172 PROCEEDINGS.
F.C.S.; ‘(OSBORNE REYNOLDS, M.A., LL.D, ERS) eae
ARTHUR SCHUSTER, Ph.D. F.RS, PR ASe ee
CosMoO MELVILL, M.A., F.L.S,
Secretaries—FREDERICK JAMES FARADAY, F.LS., |
F.S.S.; REGINALD F, GWYTHER, M,A.
Treasurer—CHARLES BAILEY, F.L.S.
Librarian.— FRANCIS NICHOLSON, F.Z.S.
Other Members of the Council—HAROLD B, DIXON,
M.A., F.R.S.; ALEXANDER HODGKINSON, MUBe oc
JAMES BOTTOMLEY, B.A., D.Sc, F.C.S.>~ All@enaaem
JOSEPH THOMPSON ; FRANCIS JONES, F.R.S, Ed., F.C. ;
W, 2. Hoven wi.
Ordinary Meeting, April 17th, 1894.
Professor ARTHUS SCHUSTER, Ph.D.,. F.R.S;5 eRe
President, in the Chair.
The thanks of the members were voted to the donors of
the books upon the table. |
Professor DIXON, M;A., F.R.S., read a paper “On the
Instantaneous Pressures produced in the Explosion-Wave.”
PROCEEDINGS. 173
[Microscopical and Natural Hzstory Sectzon.|
Annual Meeting, 9th April, 1894.
Mr. R. E. CUNLIFFE, President of the Section, in the
Chair.
Mr. BROADBENT described some observations on fission
in the Infusoria.
Mr. OLDHAM exhibited some bird snares used by the
inhabitants of the island of St. Kilda for capturing the
Fulmar Petrels and the Puffins. Also the oil vomited by
the Fulmar when captured, and the receptacle made from
the crop or stomach of the guillemot, in which the islanders
collect the oil. This oil was formerly used as a specific for
rheumatism and for dipping sheep.
Mr. ALLEN showed a specimen of alloy made from 60
per cent of copper and 4o per cent of manganese, and
described a number of observations on the injurious
effects of noxious vapours brought by prevalent winds from
manufacturing towns.
The Annual Report of the Council, and the Treasurer’s
Financial Statement, were presented and adopted.
The following gentlemen were elected Officers and
Council for the ensuing Session :—
President.—JOHN BOYD.
Vice-Prestdents—PETER CAMERON, F.E.S.; ROBERT
BELLIS: CUNLIFFE ; JAMES CosMO MELVILL, M.A., F.LS.
- Treasurer—MARK STIRRUP, F.G.S.
Secretary THEODORE SINGTON.
Council—_CHARLES BAILEY, F.L.S.; GEORGE HARRY
BROADBENT; .M.R-C.S.; °. HERBERT C. ,CHADWICK,
F.R.M.S.; ROBERT DUKINFIELD DARBISHIRE, B.A.,
m.G.s, F.S.A..; ALEXANDER. HODGKINSON, M.B., B.Sc. ;
HENRY HYDE; FRANCIS NICHOLSON, F.Z.S.; .THOMAS
ROGERS.
sy
M
174. Mr. H. B. DIXON AND MR. J. C. CAIN on the
On the instantaneous pressures produced in the
Explosion-Wave. By H. B. Dixon, F.R.S., Pro-
fessor of Chemistry, and J. C. Cain, B.Sc., 1851
Exhibition Scholar in the Owens College.
(Rececved May 22nd, 1894).
The problem of directly measuring the pressure pro-
duced in the ‘ explosion-wave’ of a mixture of gases is one
of great difficulty. The movement of the wave is so rapid,
and the zone of high temperature so thin, that the high
pressure over any given area lasts an exceedingly short
time. Nevertheless the problem is one of great importance
for the elucidation of the phenomena of explosion.
To take one instance: If the pressure produced in the
explosion-wave could be accurately measured it would
decide between the two theories of gaseous explosions that
have been put forward. According to M. Berthelot* the
velocity of explosion is equal to the mean rate of translation
of the products of combustion heated at constant pressure.
In the alternative hypothesist the velocity of explosion is
equal to the velocity of sound in the burnt and burning gas
at a temperature double that due to the combustion of the
gases at constant volume. The calculated temperatures
and pressures of the explosion-wave are very different in
the two hypotheses. For example, in the explosion of
cyanogen with its own volume of oxygen the pressure in
the wave is calculated to be 35 atmospheres according to
the first view; it is calculated to be 117 atmospheres
according to the other. In the elaborate investigation
made by M. Berthelot, in conjunction with M. Vieille, on -
the pressures produced in the explosion of gases, the
*Sur la force des matiéres explosives.
+ H. B. Dixon, Phil. Trans., vol. 184., p. 134 (1893).
Instantaneous Pressures in the Explosion-Wave. 175
pressure produced in this reaction is given as 25 atmospheres,
a number more in accordance with the first than the second
hypothesis.
But the measurements made by MM. Berthelot and
Vieille* do not, we think, apply to the pressures in the
wave. They fired mixtures of gases in a bomb and
observed the movement of a piston working against a
spring in a tube attached to the bomb. From the accelera-
tzon of the piston they calculated the pressure in the bomb.
The pressures so measured are called by Berthelot the
“effective pressures.” Now, since the .explosion-wave
travels faster than sound in the unburnt gas, the explosion-
wave is the first impulse which reaches the piston. It
follows that when the piston feels this impulse and begins
to answer to it, the explosion-wave has traversed the whole
of the gas and the true explosion is over. The piston receives
the blow of the wave and then the thrust of the expanding
gases, no doubt still combining, to a greater or less extent,
behind the wavefront. In Berthelot’s experiment, therefore,
the movement of the piston gives, in the main, the rate of
expansion of the heated gases after the explosion-wave has
passed through them: it does not give the instantaneous
pressure in the wave front itself. That higher pressures are
produced for a moment in the explosion of gases has been
proved by Mallard and Le Chatelier by the use of the
delicate indicator designed by Deprez. MM. Mallard and
Le Chatelier have also suggested a method of measuring
these pressures by the fracture of glass tubes of known
strength. This method we believe to give approximately
correct results: it depends on the principle that if a pressure
is produced in a glass tube greater than it can stand, the
glass will be broken although the pressure may only last
for a very small interval of time.
SS
* Ann. Chim. et Phys. [vi.] 4. p. 14 (1885).
176 Mr. H. B. DIXON AND MR. J. C. CAIN on the
In 1893 one of us published some preliminary experi-
ments by this method.* Tubes which stood a steady
hydraulic pressure of 25 atmospheres, were broken into
small fragments by the explosion-wave of carbonic oxide
and oxygen ; whereas, stronger tubes which stood a pressure
of 50 atmospheres were not broken by the explosion of
oxygen, either with carbonic oxide or with hydrogen; on
the other hand, the stronger tubes which had withstood 50
atmospheres on the hydraulic press, were broken by the
explosion of cyanogen and oxygen in equal volumes, and
one of these tubes was broken at 78 atmospheres on the
press. It seemed desirable to repeat these experiments
and to find, if possible, narrow limits within which the
pressure of the explosion-wave must lie.
Cyanogen was chosen as the combustible gas for most
of the experiments, because the carbonic oxide and nitrogen
yielded by its explosion with oxygen are simple in
composition and approximate in physical properties to a
perfect gas. Equal volumes of cyanogen and oxygen were
mixed in an iron gas-holder over mercury. The explosion
vessel consisted of a firing-piece with platinum wires, and
two metal tubes between which the glass tube to be tested
could be inserted by means of Faraday’s cement. After
the apparatus had been filled with gas from the holder, the
taps were closed at each end, and a spark was passed. The
explosion-wave was generated in the first metal tube and
traversed the glass tube. If the latter held it was removed
and labelled, and another tube inserted in its place. The
glass tubes were about 20 cm. in length; they were cut
from long tubes of fairly uniform bore and thickness of wall.
When a tube was broken it was our endeavour to gauge its
strength by testing hydraulically the strength of the pieces
cut on either side of it from the parent tube.
« H. B. Dixon, Phzl. Trans., Vol. 184, p. 150.
Instantaneous Pressures in the Exploston-Wave. 177
With equal volumes of cyanogen and oxygen, a very
high pressure is produced in the explosion-wave. Soda-lime
glass tubing of 18 mm. external diameter, and 2°5 mm.
thickness, was fractured by the explosion. Green glass
tubing of 28 mm. in thickness held. Experiments with
the hydraulic press showed a very considerable difference
in the strength of these tubes. Three pieces of the first
glass broke when submitted to the following pressures :—
1. 8g0 lbs. on the square inch.
Ze 950 99 >]
3: 1220 rp) bP)
mean 1020 ,, a = 70 atmospheres.
We think it safer to take the mean breaking strain of
the three pieces as representing the strength of the tubes
broken by the explosion, than to take the highest figure as
the minimum force exerted by the explosion. We thus
come to the conclusion that the pressure exerted in the
explosion-wave exceeded 70 atmospheres. Pieces of the
green glass tubing which withstood the explosion gave very
unequal results on the press :—
2050 lbs. on square inch.
2. 450 5, ”
mcan £750 ,, - = 120 atmospheres.
Unfortunately we had no other specimens of the same
kind to test. Our result, therefore, is that in the explosion
of equal volumes of cyanogen and oxygen, the pressure
produced falls between the limits of 60 to 140 atmospheres,
and more probably between 70 and 120 atmospheres.
In the next experiments, the mixture of equal volumes
of cyanogen and oxygen was diluted with its own volume
of nitrogen. The reaction occurring may be written :-—
C.N, + Og + 2N2= 2CO + 3Nz.
The “ effective pressure” produced on firing this mixture
178 Mr H..B. DIXON AND MR: J. C. CAIN on the
in a bomb has been measured by Berthelot, and found to
be 15 atmospheres. As calculated from Berthelot’s theory,
the pressure in the wave should be 18 atmospheres ;
according to Dixon 57 atmospheres. One reason which
led us to dilute the explosive mixture was suggested to us
by Professor Osborne Reynolds. If the velocity of the
explosion-wave in the gas approximates to the rate at which
the distortion-wave in the glass is propagated, the latter
might be continually re-inforced, and the tube be broken
as the result of a pressure far less than that required to
break it under other conditions. The velocity of this wave
in glass is nearly 3,000 metres per second. The rate of
explosion of equal volumes of cyanogen and oxygen is
2,728 metres per second ; when this mixture is diluted with
its own volume of nitrogen, the rate of explosion falls to
2,163 metres per second. In the diluted mixture, therefore,
there could be no question of the waves coinciding in rate.
The reduction of pressure caused by dilution made the
measurement more accurate, as it enabled us to find glass
of more nearly equal strength holding and breaking
respectively. After several trials a piece of uniform tube
was found which broke, and a slightly thicker one which
held. Two pieces of the first broke at the following
pressures :—
I. 950 lbs. on square inch.
2. 925 ;, 9 99
mean 938 ,, a is = 63 atmospheres.
Two pieces of the second broke :—
I. 1230 lbs. on square inch.
2. I250 9 +) ”
mean 1240 ,, is a = 84 atmospheres.
The lower limit viz, 63 atmospheres, is rather higher
than the pressure calculated by Dixon’s formula.
| Instantaneous Pressures in the Explosion-Wave. 179
An indirect way of arriving at the pressures in the
explosion-wave is given by Riemann’s* equation for the
propagation of abrupt variations in the density and pressure
of a gas. Professor Schuster + has given reasons for sup-
posing that Riemann’s equation applies for the explosion-
wave, and has shown a simple way of calculating the
pressures from the known velocity of the explosion-wave
and the density of the unburnt gas. According to Rie-
mann’s equation the pressure in the explosion-wave of
cyanogen and oxygen should be 135 atmospheres, and when
diluted with its own volume of nitrogen the pressure should
be 71 atmospheres. The calculated and observed pressures
may be conveniently compared in the annexed table :—
Pressures in the Explosion-wave.
CALCULATED. OBSERVED.
Gaseous Mixture. Berthelot.| Dixon. | Riemann.||Berthelot. roe
| C.Na + Oz a5 it. a7 Ate 1S5 Atl) 125 At}7o—120)
C.N,.+ O,+2N, || 18 ,, 5B | AT oll B5cen 103-84]
It will be observed that the pressures calculated by
Riemann’s equation are about 4 times greater than those
deduced from Berthelot’s Theory : and are larger (roughly
by 20 per cent) than those calculated from Dixon’s
They agree within the limits of error with our observations
on the breaking strain of glass tubes.
Experiments on the Collision of Two Explosion-waves.
The apparatus we employed could readily be adapted
to observe the effect of bringing two explosion-waves into
collision. Will the result of two waves meeting from
* *Gottingen Abhandlungen.’ 8. (1860).
+ Vide Phil. Trans. Vol. 184, p. 152. (1893).
180 Lnstantaneous Pressures zr the Explosion-Wave.
opposite directions be to largely increase the pressure at the
point of contact? By analogy one might suppose that such
would be the case; but, on the other hand, since the
explosion travels much faster than any wave in the unburnt
gas the explosion-wave is always, as it were, dashing on a
dead wall and piling up pressure, and no further effect, it
might be argued, could be produced when it meets and is
repulsed by a similar wave. It seemed, however, possible
if the wave is propagated partly by the movement of heated
yet unburnt molecules in the wave front—that ¢hese mole-
cules on coming into collision would cause a measurable
increase of temperature and pressure in the wave. We
have not been able to measure any such increase by this
rough method of trial. The explosion tube, some
3 feet from the firine ‘point, bifurcated )intese ges
arms like the letter Y. The two arms were bent round
nearly to meet, and the junction was effected by a piece of
glass tube inserted in the gap. The centre of the glass
tube was exactly equi-distant from the fork by either arm ;
consequently the explosion-wave, dividing into two at the
fork, traversed the two arms and came into collision in the
middle of the glass tube. By a suitable tap, one arm could
be closed, and the explosion then traversed the glass tube
only in one direction. Experiments made with hydrogen
and oxygen, with equal volumes of cyanogen and oxygen,
and with the same mixture diluted with nitrogen as before,
showed no appreciable difference between the pressures
produced in the glass tube when the flame went in
one direction only and when the two explosion-waves met
end on. Pieces of the tube, which broke in the hydraulic
press at 63 atmospheres, broke both ways equally in the
explosion apparatus: pieces of the tube, which broke
in the hydraulic press at 84 atmospheres, stood the
explosion both ways equally. If the collision had caused
the pressure to rise by 14 we ought to have detected it.
Coast Lines and Magnetic Declination. 181
On the Influence of the Configuration and Direction
of Coast Lines upon the Rate and Range of the
Secular Magnetic Declination. By Henry Wilde,
F.R.S.
(Recezved April 3rd, 1594.)
In a paper which was read before the Royal Society in
June, 1890, I showed that the principal phenomena of
terrestrial magnetism and the secular changes in its
horizontal and vertical components could be explained on
the assumption of an electro-dynamic substance (presumably
liquid or gaseous) rotating within the crust of the earth in
the plane of the ecliptic, that was to say, at an angle of
23°°5, and a little slower than the diurnal rotation. By
means of some electro-mechanism, new to experimental
science, which I termed a Magnetarium, the period of
backward rotation of the electro-dynamic sphere required
for the secular variations of the magnetic elements on
different parts of the earth’s surface was found to be 960
years, or 22°5 minutes =0'375 annually.
From the relations of a magnetic needle on the earth’s
surface, and an electric current circulating round the
internal electro-dynamic sphere, it will be obvious that the
magnetism of such a system would be symmetrically
distributed, with similar lines of declination and inclination
on meridians and parallels 180° from each other. An
examination, however, of the lines of declination over the
terrestrial globe, as determined by careful and repeated
observations, exhibits wide divergencies from the sym-
metrical lines of declination obtained with the. electro-
dynamic sphere alone,
Thus, there are on the variation chart (Plate X.) four
182 Mr. HENRY WILDE oz
well-defined lines of no declination in the northern hemi-
sphere, for two similar lines of no declination in the southern
hemisphere. The declination also varies very considerably
for equal latitudes and longitudes in the northern and
southern hemispheres, for the same or for different epochs.
This is seen in the large amount of the declination at the
Cape of Good Hope, and the small amount on the great
land areas of Eastern Europe and Asia, as well as over
the Eastern States of North America. The comparatively
small area, or oval, of westerly declination in Eastern
Asia, surrounded by considerable areas of easterly variation,
together with the closed curve of small easterly variation in
the equatorial parts of the Pacific, contributes still further
to increase the difficulty of the problem of reducing the
distribution of the earth’s magnetism to general laws.
The unsymmetrical character of the lines of equal variation,
and the devious courses of the lines of equal inclination and
the magnetic equator, are no less perplexing to magneticians
than the irregularities of the declination at different epochs
for equal latitudes.
In the course of my experiments, it was noticed that the
lines of no declination of the internal sphere of the magnet-
arilum were generally in advance of those on the charts for
a given epoch. Thus the two antartic lines of no declination
were more than 40’ east of the similar lines of the electro-
dynamic sphere for the epoch 1880.
With the object of ascertaining what influence the
configuration of the surfaces of the terrestrial globe, as
indicated by the general distribution of land and water,
had on the magnetic elements, the ocean areas of the outer
globe of the magnetarium were covered with thin sheet
iron roughly contoured to the coast lines in both hemi-
spheres. On turning the internal electro-dynamic sphere
84° W. to correspond with the epoch 1880, a remarkable
change in the magnetic elements was manifested. The two
Coast Lines and Magnetic Declination. 183
lines of no declination in the southern hemisphere of the
outer globe were nearly coincident with those on the chart;
and in the northern hemisphere four zero lines appeared
similarly coincident ; two of which lines on the North
American and European continents were continuations of
those in the southern hemisphere. But the most remark-
able and unexpected feature of the distribution of the
magnetism on the iron-covered globe was the reproduc-
tion of the oval area of small westerly declination in
Eastern Asia (110 —160° E.), surrounded by large areas
of eastern declination. The oval also agreed in detail with
that on the chart in having the largest westerly declination,
about 8° in the centre, between the lines of no declination.
Scarcely less interesting was the unlooked-for reproduc-
tion of the oval area of small easterly declination, about 5°,
surrounded by a large area of greater eastern declination
in the equatorial parts of the Pacific (120°—170° W.), while
the unsymmetrical form of the magnetic equator was very
similar in its deviations to that of the earth for the epoch 1880.
Further experiments with the iron-covered globe showed
that the land areas, besides retarding the translatory
movement of the lines of thedeclination, generally diminished
the amplitude of the declination itself, and to a greater
amount as the broad features of the continental coast lines
extended more or less in a direction parallel to the earth’s
equator.
On the other hand, continental coast lines extending
more or less parallel to the earth’s axis and terminating in
capes or headlands, diminish the horizontal force, and,
consequently, increase the rate and range of the declination ;
as instanced :—(1) In the large amount of the secular change
along the South African coasts, where at the Cape of Good
Hope the declination is 30°W. (2) On the South American |
coasts about Cape Horn, 20°E. (3) Onthe Greenland coasts
at Cape Farewell, 50°W. (4) The coasts of Southern India
184 Mr. HENRY WILDE oz
at Cape Comorin, where the declination was 16°W. in the
year 1601, and is now I°E. vy
The observations of deep-sea temperatures made during
recent years have brought out the important fact that, at
great depths, the temperature of the ocean beds is little
above the freezing point of water. Prestwich and others
have inferred that this low temperature of ocean depths is
competent to produce a greater thickness of the earth’s
crust under the oceans than under the land. The large
amount of iron which enters into the composition of the
earth’s crust is well known from the analysis of volcanic
ejections from all parts of the globe, while at extreme
depths this element exists in the metallic state, as at
Ovefak, off the coast of Greenland, where it is found
diffused in the basaltic rocks and in separate masses. We
have, therefore, through the low temperature and increased
thickness of the ferruginous ocean beds, the precise con-
ditions required for producing the differences in the
magnetic elements which have been shewn on the mapped
globe when the ocean areas were covered with iron.
Now that the great influence which the land areas
exercise in retarding the translatory motion of the lines of
the declination has been shewn, which is distinct from the
magnetism of local geological formations, the same
influence in determining the form and position of the
declination lines on the terrestrial surface becomes very
apparent on the charts. An important negative feature of
this influence is the symmetry and simplicity of the declina-
tion lines in the southern hemisphere, where the ocean
completely encircles the globe in latitude 60°, as compared
with the devious lines of the declination on the great land
areas in the same latitude of the northern hemisphere.
The dominant influence of longitudinal coast lines is
well seen in the bend of the zero and other declination lines
towards the north pole of the earth’s axis in their westerly
Coast Lines and Magnetic Declination. 185
march over Europe ;—the effect of the intersection of the
land areas by the basin of the Mediterranean and other
great inland depressions, extending more or less parallel to
the equator over 60° of longitude. The polarising effect
of the arctic coast line appears in the small amount of the
declination at St. Petersburg, which has not varied more
than 8° during the last 150 years. The polarisation of the
coast lines is again seen on the chart at the shoulder of the
South Amerian continent at Pernambuco, where the lines
bend upwards towards the polar axis, and resume their
westerly direction in the Carribean Sea and in the basin of
the North Atlantic. Strong polarising effects, to diminish
and retard the declination, are also produced by the
longitudinal coast lines of the Gulf of Mexico, the West
Indian Islands, the north and south coasts of Australia, the
great coast lines within the Antarctic circle, the Malayan
Archipelago and the southern coasts of India and China.
So great is the polarity of the West India Islands, that
the secular change of the declination at Jamaica and Cuba
has not amounted to more than 3° during the last 200
years. From a comparison of the zero lines of declination
of the internal electro-dynamic sphere in relation to the
earth’s axis and to the zero lines on the terrestrial surface,
it will be seen that the appellation of magnetic poles and
zeros of declination applies with strictness only to the poles
of the earth’s axis, and to the poles and meridians of the
internal electro-dynamic sphere, as the zeros of declination
on the earth’s surface, for the present epoch, are generally
the resultants of the changing electro-dynamic and
permanent magnetic forces acting through and upon the
outer crust of the terrestrial globe.
An interesting instance in confirmation of my views and
experiments on the polarising action of longitudinal coast
lines which I desire to bring before the Society, on account
of its importance to practical navigation, was brought to
186 Coast Lines and Magnetic Declination.
light during the Admiralty enquiry into the causes that
led to the disastrous loss of H.M.S. “Serpent” off Cape
Villano, on the coast of Spain, November, 1890.*
Among other reports read before the Court was one from
the captain of the Spanish screw steamer “ Beneta,”’ who
stated that, during the 15 years he had been trading along
the north coast of Spain, he did not remember to have
observed any deviation of the compass on account of the
attraction of the iron ore mountains, but he always noticed
that when steering on a southerly course the error of the
compass was N.E.; that was to say, that the local variation
of the compass was eight or ten degrees N.W. instead of
18 or 20 degrees as shown on the Admiralty chart of the
declination. Now, a glance at the chart will show that the
north coast of Spain extends parallel to the earth’s equator
for a distance of nearly eight degrees, or 400 miles, and
has, consequently, a maximum polarising influence on the
compass to diminish the amount of the secular change of
the declination, as observed by the captain of the “ Beneta”
and as set forth in my papers.
It would therefore appear that some of the declination
lines, as represented on the charts, do not partake of that
symmetrical character that is generally accorded to them
and that caution will be required in the use of variation
charts off the greatly extended coast lines of deep seas
where the rate and range of the secular declination are
large in amount.
* The London Zzmes, December 17th, 1890.
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F32 eARME ADEE RATA TS CEL Sef FE IE pa
D.C.L., LE.D., F: RS;
Savilian Prof. of Geom. in the Univ. of Oxford, Cor.
Mem. Inst. Fr. (Acad. Sci.), &c. Mew College, Oxford.
Tait, Peter Guthrie, M.A., F.R.S.E., &c., Professor of
Natural Philosophy, Edinburgh. 38, George Square,
Edinburgh.
Thorpe, T. E., Ph.D., F.R.S. Laboratory, Somerset House,
London, W.C.
Trécul, A., Membre de Il’Institut. Parzs.
Turner, Prof. Sir Wm., F.R.S. Edinburgh.
‘iylor; Edward: Burmett, F.k.S., D.C.L. (Oxon), LED:
(St. And. and McGill Colls.), Keeper of University
Museum. Oxford.
Radcliffe Observatory,
Vines, Sidney, Professor of Botany, F.R.S. Headington
fill, Oxford.
Waage, Professor P. Christiania, Norway.
Walker, General Francis A., Professor of Political Economy.
237, Beacon Street, Boston, U.S.A.
Warburg, Professor E. 8, Goethestrasse, Freiburg, Baden.
Ward, Professor H. M., F.R.S. Cooper's Hill, Englefield
Green, Surrey.
Weismann, Professor August. retburg, Baden.
Wiedemann G., Prof. of Physics, For. Mem. R.S. 35,
Thalstrasse, Letpsic.
Williamson, Alexander William, Ph.D., LL.D., F.R.S.,
Corr. Mem. Inst. Fr. (Acad. Sci.). Aigh Pitfold, Shotter-
mill, Haslemere.
Williamson, Wa -C., LL.D.,
Clapham Common, London.
Young, Prof. C. A. Princeton College, N. J., U. S.A.
F.R.S.- 43) 2772s Koad,
Zirkel, Ferdinand, Professor of Mineralogy. Unversity of
Letpsic.
Date of Election.
1870. March 8.
1866, Jan. 23.
1861, April 2.
1849, April 17.
1850, April 30.
1882, Nov. 14.
1859, Jan. 25.
1857, Jan. 27.
Corresponding Members.
Corresponding Members.
Cockle, The Hon. Sir James, M.A., F.R.S., F.R.A.S.,
F.C.P.S. 12, St. Stephen’s Road, Bayswater, London.
De Caligny, Anatole, Marquis, Corres. Mem. Acadd. Se.
Turin and Caen. Socc. Agr. Lyons, Sci. Cherbourg,
Liége, &c.
Durand-Fardel, Max, M.D., Chev. of the Legion of
Honour, &c. 36, Rue de Lille, Paris.
Girardin, J., Off. Legion of Honour, Corr. Mem. Instit.
France, &c. Lille.
Harley, Rev. Robert, M.A., F.R.S. Savile Park, Halifax,
Yorks.
Herford, Rev. Brooke, 91, Fitzjohn’s Avenue, Hampstead,
London, N. W.
Le Jolis, Auguste-Francois, Ph.D. Archiviste perpétuel
and late President of the Soc. Nat. Sc., Cherbourg, &c.
Cherbourg.
Lowe, Edward Joseph, F.R.S., F.R.A.S., F.G.S., Mem.
Brit. Met. Soc., &c. Shirenewton Hall, near Chepstow.
Date of Election.
1870, Dec. 13.
1861, Jan.
1837, Aug.
1881, Nov. I.
1887, Nov. 16.
1865, Nov. 15.
1888, Nov. 13.
1888, Feb. 7,
1894, Jan. 9.
1868, Dec. 15.
1861, Jan.
1875, Nov. 16.
1889, Oct. 15.
1894, Mar. 6.
1855, April 17.
1861, April 2.
1844, Jan. 22.
1889, April 16.
1860, Jan. 23.
1886, April 6.
1846, Jan. 27.
1889, Jan. 8.
1880, Oct. 15.
1872, Nov. 12.
1893, April 18.
1854, April 18.
1884, Nov. 4.
1853, Jan. 25.
1893, Jan. 10.
1859, Jan. 25.
1876, April 18.
Ordinary | Members. 233
Ordinary Members.
Angell, John, F.C.S., F.I.C. 6, Beaconsfield, Derby Road,
Fallowfield, Manchester.
Anson, Rev. George Henry Greville, M.A. Sirch Rectory,
Rusholme.
Ashton, Thomas. 36, Charlotte Street.
Ashton, Thomas Gair, M.A. 36, Charlotte Street.
Ashworth, J. Jackson. 39, String Gardens, City.
Bailey, Charles, F.L.S.