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quotient " has been also termed " the worth " of a corpuscle.^

The more exact methods for the determination of the amount of haemo-
globin in blood are dealt with elsewhere (see article on Hsemoglobin). For
clinical purposes a comparison with a standard colour of the colour of the
blood diluted to a known amount is found to give sufficiently accurate results.
The chief methods used have been— (1) That of Gowers,^ who employs picro-
carmine gelatin as a standard ; (2) that of F. Hoppe-Seyler,^ who combines
the hsemoglobin with carbonic oxide, and compares it with a standard solution
of CO haemoglobin ; and (3) that of v. Fleischl, who used a wedge of tinted
glass as a comparison. The method of v. Fleischl is by far the most con-
venient. It has been greatly improved by Oliver, who has adapted to it
the principle of Lovibond's tintometer.^ Thus modified it takes the form of
a series of tinted glasses, one of which represents accurately the colour of a
measured amount of normal blood diluted with water and placed in a flat
glass cell of a certain size, whilst the others represent percentages of heemo-
globin below and above the normal (Fig. 22). The blood is measured in a
pipette similar to that shown in Fig. 21, a.^

The number of white corpuscles in a cubic millimetre of blood is
usually stated as 10,000, but it varies greatly even in health. By far
the larger proportion (70 to 90 per cent.) are of the finely granular
oxyphil variety.^ Of the rest less than 5 per cent, are coarsely granular
oxyphil cells, while the remainder, except a few which are hyaline,
contain basophil granules.

Injection of many substances (peptones, nuclein, leech extract) into
the vessels causes an immediate and marked diminution in the number
of the leucocytes, chiefly affecting the finely granular kind {lcucocyto])enic
phase, Lowit) ;^ it is followed by an increase in their number (leucocytotic
phase). Acute local inflammation causes similar changes, but the
diminution in the number of leucocytes also largely affects the coarsely
granular cells, whereas the after increase is mainly in the finely
granular. Hankin noticed that the blood clots more readily when the
coarsely granular cell is scanty ; this may explain the more ready
clotting of blood in inflammatory conditions.

The blood possesses, in the presence of free oxygen, a certain power of
producing oxidation in readily oxidisable substances, which may be added to
it, such as salicylaldehyde.^ This property it shares Avith some of the
tissues (sjDleen, liver, lung, thyroid, kidney, thymus), while other tissues
show no such tendency (muscle, brain, pancreas). The oxidation power is
greater in young subjects than in the adult.^^ On the other hand, the blood
contains a substance or substances (" reducing substances " of Pfliiger) which
greedily appropriate any free oxygen which may be present in the plasma,

^ Oliver, loc. cit., p. 1705.

- Garrod, Med.-Chir. Trans., London, vol. Ixxv. p. 191.

^ Lancet, London, 1878, vol. ii. p. 822.

'' Ztschr. f. 2Jhysiol. C'hem., Strassburg, Bd. xvi. S. 505. See also G. Hoppe-Seyler,
ibid., 1890, Bd. xxi. S. 461, and Winternitz, ibid., S. 468.

^ Lovibond, "Measurement of Ligbt and Colour Sensations."

® For more complete details of the method see Oliver, loc. ciL, pp. 1699-1703.

^ Sherrington, Proc. Roy. Sac. London, 1894, vol. Iv. ; Kanthack and Hardy, Journ.
Physiol., Cambridge and London, 1894, vol. xvii. p. 81. Tlie earlier literature is given by
Sherrington.

8 "Studien z. Phys. n. Path. d. Blutes," Jena, 1892.

»Salkowski, ZL'^chr. f.2)hysiol. Chem., Strassburg, 1882, Bd. vii. S. 115 ; Centralbl. f.
d.med. TFissensch. , Berlin, 1892, Bd. xxx. S. 489.

1" Abelous and Biarnes, Arch, de j^ihysiol. norm, etpath., Paris, 1895, pp. 195 and 239.



GENERAL COMPOSITION.



153



and. are even capable of abstracting the oxygen which is combined with
hsemoglobin, so that arterial blood rapidly becomes converted into venous
blood, when it is not exposed to the access of fresh oxygen. It is not known
upon what substance or substances these properties depend, but it is prob-
able that it is a function of the protoplasm of cells, and, in the case of the
blood, it may be due to the protoplasm of the white corpuscles.

General composition. — The general composition of blood and the
relative distribution of its constituents in the corpuscles and plasma
respectively is illustrated in the accompanying tables from C. Schmidt ^
and Bunge. ^



Venous Blood of a Man, cet. 25


, sp. gr.


1-0599


(C. Schmidt)




In 1000 grms. blood corpuscles (sp. gr. 1-0886) —
Water .....




681-63


Substances not vaporising at 120° C.




318-37


Haemoglobin and other proteid substances




311-09


Inorganic substances —






Chlorine . . . .


1-750




Sulphuric acid .






0-061




Phosphoric acid .
Potassium






1-355
3-091




Sodium






0-470




Phosph. lime






0-094




Phosphate magnesia
Oxygen .






0-060
0-401




Total of inorganic constituents (exclusive of iron


)


7-282


In 1000 grms. plasma (sp. gr. 1-0312)—

Water .....




901-51


Substances not vaporising at 120° C.

Fibrin .....




98-49
8-06


Other proteids and organic substances .




81-92


Inorganic substances —






Chlorine . .


3-536




Sulphuric acid .
Phosphoric acid .
Potassium






0-129
0-145
0-314




Sodium .






3-410




Phosphate lime .
Phosphate magnesia
Oxygen .

Total of inoreanic co


nstituen


its


0-298
0.218
0-455


8-505



In this estimation the phosphoric acid is probably too high, being
increased in the process of calcining by the phosphorus in the lecithin.
SertoH,^ by eliminating this error, obtained only 0-025 grm. phosphoric
acid per 1000 grms. ox serum, equivalent to only O'OOS per cent, hydro-
disodic phosphate (]S[a2HP04).

It is clear from the foUov^ing table that there are considerable
differences in the composition of the whole blood and of its parts in

1 "Charakter. der epid. Cholera," Leipzig, 1850.

" Ztschr. f. Biol., Miinchen, 1876, Bd. xii. S. 191; and "Physiol, and Pathol.
Chemistry," trans, by Wooldridge, 1890, p. 245.

''Sertoli in Hoppe- SeyUr s Mad. Chem. Untersuch., Berlin, 1868, S. 352. See also
Miroczkowski, Centralhl. f. d. med. Wissensch., Berlin, 1878, S. 353, who obtained in calf
serum, O-QIS ; in sheep serum, 0.0092 and 0-0064 ; and in dog serum, 0-0083 parts
Na.^HPO^ per 100 serum.



154



THE BLOOD.



different species of animals. In most animals the IjIoocI corpuscles have
a relatively large proportion of potash salts and phosphates, whereas
the preponderating salt in the serum is sodium chloride. In the Ijullock,
however, this salt also occurs m large amount in the corpuscles.



Defibrinated Blood of Pig, Horse,


and Bullodc (Bunge).






In 1000


Grms. Cor


PUSCLES.


Ik 1000 Grms. Serum.


Pig.


Horse.


Bullock.


Pig.


Horse.


Bullock.


"Water


632-1


608-9


599-9


919-6


896-6


913-3


Solids


367-9


391-1


400-1


80-4


103-4


86-7


Proteids, including bamoglobin


347-1




387-8


67-7




73-2


Other organic substances


12-0




7-5


5




5-6


Inorganic substances




8-9




4-8


7-7




7-9


K„0






5-543


4-92


0-747


0-273


0-27


0-254


Xa.,0 .










2-092


4-272


4-43


4-351


CaO












0-136




0-126


MgO .






0-158




0-017


0-038




0-045


Fe,03 . . .
















0-011


CI . . .






i-504


1-93


1-635


3-611


3-75


3-717


P.O. . . .






2-067




0-703


0-188




0-266



In the pig's blood analysed, there were, in 1000 parts, 436-8 corpuscles, and
563-2 serum.

In the horse's blood analysed, there were, in 1000 parts, 531-5 corpuscles,
and 468-5 serum.

In the bullock's blood analysed, there were, in 1000 parts, 318-7 corpuscles,
and 681-3 serum.

A. Schmidt, in conjunction with his pupils,^ got the following results
from analyses of human blood obtained by venesection.



Serum
Corpuscles
Total blood



Percentage
Amount.



52-120

47-880



I Amount of
Specific Dry Residue
Gravity. 1 "in lOQ
Grms.



1028-3



1060-7



9-709
35-458
21-971



Amount of Na, K, and CI, in
100 grms. (Warnach).

i


Na.


K.


CI.


0-344


0-02


0-353


0-282


0-307




0-185


0-182


0-259



Gases of the blood. — Arterial blood of the dos; contains from 15 to
25 vols, per cent, oxygen (at 0'' C. and 760 mm. pressure), 25 to 40 car-
bonic anhydride, and about 1-8 vols, per cent, nitrogen. Venous blood
of the same animal contains from 5 to 15 vols, per cent, oxygen, 38 to
52 carbonic anhydride, and also about 1*8 vols, per cent, nitrogen.'-^ The
proportions of these gases and the manner in wdiich they are combined
with constituents of the corpuscles and plasma is discussed elsewhere."



' Arrouet, Diss., Dorpat, 1837 ; Warnach, Diss., Dorpat, 1888.

- Schofier, Sitzunrjsh. d. l\ Akcul. d. Wisscnsch., Wien, 1860, Bd. xli. S. 589 ;
Sczelkow, ibid., 1862, Bd. xlv. S. 171 ; Pfliiger, Arch. f. d. ges. FhysioL, Bonn, 1868, Bd.
i. S. 275.

^ See " Chemistry of Respiration."



COMPOSITION OF RED CORPUSCLES.



155



The red corpuscles. — These consist of a delicate external envelope
enclosing coloured fluid contents.^ In all vertebrates below mammals
they contain a nucleus, the chief chemical constituent of which is
nuclein (see p. 65).

The organic matter in one hundred parts of dried red corpuscles
consists of : ^ —





Human


Blood.


Dog's Blood.


Goose's Blood.


-


11.


I.


Proteids and










nuclein .


12-24


5-10


12-55


36-11


Hpemoglobin


86-79


94-30


86-50


62-65


Lecithin


0-72


0-35


0-59


0-46


Cholesterin


0-25


0-25


0-86


0.48



Goose's blood was taken as an instance of one in which nucleated
red corpuscles are present ; the higher percentage of proteids apparent
in this is due to the included nuclein.

The mineral constituents of the red corpuscles vary greatly in
relative quantity in different species of animals. Thus potassium con-
stitutes 40-89 per cent, of the total ash of human red corpuscles, and
sodium only 9-71, whereas in the dog the percentage of potassium is
6'07, and of sodium 36'17 (C. Schmidt).

The remarkable excess of potassium over sodium salts is the opposite to
their relative proportion in plasma.

The chief organic constituent of the corpuscles, liEemoglobin, will be
considered in a separate article. The other organic constituents consist
of nucleo-proteid, lecithin, and cholesterin.

The, imideo-proteid of the red coijniscle. — Wooldridge's ^ method for
obtaining the nucleo-proteid consists in centrifugalising defibrinated
blood repeatedly with a 1 per cent, sodium chloride solution until all
the sermii is washed away. The red corpuscles are then laked by
the addition of water, and the mixture is shaken with a Httle ether,
to assist the solution; the white corpuscles are allowed to settle,
or removed by the centrifuge. To the clear but highly coloured
decanted fluid a little 1 per cent, solution of acid sodirnn sulphate is
added. This causes a considerable precipitate of nucleo-proteid, which
is chiefly derived from the red corpuscles, but a small part of which
may come from the white corpuscles and blood platelets.

The material thus obtained was shown by Kiihne,* who used a rather
different method of separating it, to possess fibrino-plastic properties. It
was further examined by Halliburton and Friend,^ who found that it was

1 Schafer in Quain's "Anatomy," 10th edition. 1893, voL i. pt. 2, p. 210.

^ Hoppe-Seyler and Jlidell, Med. Ghem. Untersuch., Berlin, 1866, Heft 3. Manasse,
Ztschr. f. 2}hysiol. Chem., Strassburg, Bd. xiv. S. 452, gives the following percentages —
Lecithin, 1-687; Cholesterin, 0-151.

^Arch.f. Physiol., Leipzig, 1881, S. 387.

^ "Lehrbuch," S. 193.

° Journ. Physiol., Cambridge and London, 1886, vol. x. p. 532.



156 THE BLOOD.

identical in properties with what had been called by Halliburton cell
globiiHn-/S (see p. 82). When cell globiihn-|3 was cliscovered to be a
nucleo-proteid, this also was found to be of the same nature.^ It can
also be prepared from the red corpuscles by Wooldridge's acetic-acid
method, or, provided the corpuscles are well caked together by the action
of an efficient centrifuge, by the sodium-chloride method of Halliburton.
In these experiments the colourless corpuscles may be got rid of by a
previous injection of commercial peptone.

In cats the percentage of phosphorus in the corpuscular nucleo-proteid
is 0'68. It produces intravascular coagulation when a 'solution in 1 per
cent, sodium carbonate is injected intravenously (Halliburton).

The lecithin and cholesterin. — L. Hermann ^ and Hoppe-Seyler ^
described the phosphorus-containing organic constituent of the cor-
puscle as protagon, a substance got in large quantities from medullated.
nerves, but subsequently it was recognised by Hoppe-Seyler ^ to be in
reality lecithin, which is a decomposition product of protagon (see p. 83).
Both lecithin and cholesterin are extracted from the corpuscles by ether,
and are therefore either free or, at most, in very loose combination
with the nucleo-proteid.

The chemical composition of the white corpuscles has been
already dealt with (p. 83).

The blood platelets. — In spite of the large amount of research from
the histological standpoint which has been carried out in relation to the
blood platelets {Blutpldttchen of Bizzozero), very httle is known about
theu^ function or their chemical composition. According to Lowit,^
they consist chiefly of a globulin, and plaj^ an important part in
fibrin formation. As the result of microchemical work, Lihenfeld^
considers that they consist of nucleo-proteid.

Lowit states that they are not to be seen in the circulating blood,'^
and regards them as being produced partly from the white corpuscles,
partly from globulins of the plasma, after withdrawal of the blood.
They can, however, be seen within capillary blood vessels which have just
been removed from animals, and in which the blood is still fluid.^
Mosen failed to find them in lymph.^

Their number in the blood has been variously estimated at from
180,000 to over 600,000 per c.mm.io

Blood Plasma.

The methods of obtaining plasma from blood, by preventing coagula-
tion and allowing the corpuscles to subside, have already been given.
Obtained thus from a suspended vein or from a cooled vessel, plasma

^ Halliburton, Journ. Physiol., Cambridge and London, 1895, vol. xviii. p. 306.

- Arch. f. Anal. u. Physiol., Leipzig, 1866, S. 33.

'^ Med. Chem. Untersuch., Berlin, Heft 1, S. 140.

^ Ihid., Heft 3.

° Arch. f. exper. Path. u. Pharmakol., Leipzig, 1888, Bd. xxiv. S. 188.
. fi Arch./. Physiol, Leipzig, 1892, S. 115.

"^ Virchovfs Archiv, 1889, Bd. cxvii. S. 545 ; and "Studien z. Phys. u. Path. d. Blutes
u. d. Lyraphe," Jena, 1892.

•* Osier, Proc. Roy. Soc. London, 1874, No. 183. Tliis observation I can entirely confirm.

^ Arch./. Physiol., Leipzig, 1893, S. 352. See also Druebin, 1892, ibid., Suppl., S.
211.

1" See on this subject, Muir, Journ. Anat. and Physiol., London, 1891, vol. xxi. ; also
Brodie and Kussell, Jov.rn. Physiol., 1897, vol. xxi. p. 390, who give reasons for regarding
the higher number as more correct. Probably, however, the number varies gi'catly.



INORGANIC SUBSTANCES. 157

is a clear yellowish liquid of alkaline reaction and sp. gr. about 1027-1031,
It contains about 90 per cent, of water, holding various organic and
inorganic substances in solution. With the exception of certain proteids,
the constituents of plasma are identical with those of serum, in which
they are more readily studied.

Inorganic substances. — Plasma consists to about 90 per cent, of
water. The inorganic salts occur to the amount of about 0'8 per cent.
The principal is chloride of sodium. This can be crystalhsed out from
plasma after inspissation. According to the analyses of C. Schmidt, it
is present to the extent of 0"55 per cent. Carbonate of soda is probably
the next most abundant salt, although its exact amount cannot be stated.
It is to this salt that plasma mainly owes its alkalinity and its power of
absorbing carbonic acid. Although it is not possible to state definitely
in what manner the acids and bases of the plasma are distributed, it
appears probable that, besides these two salts, chloride of potassium,
sulphate of potassium, phosphate of calcium, phosphate of sodium, and
phosphate of magnesium, and probably chloride of calcium, occur ^ in
small amounts. Traces of a fluoride have also been found."^

Gases. — The gases of plasma have not been satisfactorily investi-
gated. They are probably not very different from those of serum,
which in the dog consist of from 43 to 57 vols, of carbonic anhydride,
2"25 of nitrogen, and 0'25 of oxygen.^ The oxygen and nitrogen are
probably simply dissolved in the plasma, but the carbonic anhydride
is present in far too great an amount for this to be the case, since
not more than 2 or 3 vols, per cent, of this gas could be dissolved. The
remaining amount must therefore be in chemical combination. This can
only be with soda, as carbonate and bicarbonate ; for other bases are
present in too small amount in plasma to be taken into serious considera-
tion. This statement is also true for alkaline phosphates, although in
the corpuscles, in which they are present in considerable quantity, they
may play an important part in fixing CO2 (Bunge), as shown by the
following equation : —

Na2HP04 + H3CO3 = H2PO4 + NaHCOg.

Some of the CO2 may be combined with proteid,^ but this can only be
very little. As a matter of fact, Bunge calculates that, after allowing
for the amount of soda required to saturate the only strong mineral acid
of the plasma (hydrochloric), there is enough left to fix 63 vols, per cent,
of CO2 as carbonate, and an equal additional amount as bicarbonate,
which is far more than the amount of CO2 actually present.^

Organic constituents of blood plasma. — The organic constituents
of plasma may be divided into proteids and non-proteids, and the latter
into nitrogenous and non-nitrogenous.

Non-nitrogenous organic substances found in plasma. — These
consist of carbohydrates and fats ; and, in addition, there are present
small quantities of a lipochrome, of cholesterin, and probably of sarco-
lactic acid.

Carhohydrates of plasma. — Three carbohydrates have been described

^ Pribram, Abhandl. d. math.-phys. CI. d. k. Scichs. GeseUsch. d. Wissensch., Math.-phys.
Klasse, 1871, Bd. xxiii. S. 279 ; and in Ari. a. d. pliysiol. Anst. zu Leipzig, 1871, p. 63.
- Tammann, Ztsclir. f. 2^hysiol. Chem., Strassburg, 1888, Bd. xii. S. 325.
^ Bunge, op. cit. , S. 286.

•* Sertoli, Hoppe- Seijler s Med. Chem. Untersuch., Berlin, 1868, Heft 3, S. 350.
5 Op. cit., S. 286.



158 THE BLOOD.

in plasma, namely — (1) glycogen ; (2) an animal gum ; (3) dextrose or
grape sugar.

1. Glycogen. — There seems to be no doubt that traces of glycogen can
be obtained from fresh blood. Some is said to occur free in plasma, but
if so it is probably derived from intermixed or disintegrated leucocytes,
which can be shown by histochemical reaction to contain it.^ Kaufmann
finds the amount of glycogen in blood to be greatly increased (from 0-025
to 0-59 per litre) by removal of the pancreas.^

2. Animal gum. — Freund ^ has obtained from blood a carbohydrate
substance, resembhng that described by Landwehr under the above name.
It has the formula (CeHioOj)^, and is converted by boihng with dilute
mineral acids into a substance (sugar) which reduces Fehling's solution,
but is not fermentable, nor is it rotatory for polarised Hght. Four htres of
ox blood yielded 0-82 grms. of the gum, giving a percentage amount of 0-02.

3. Dextrose. — This is a constant constituent of plasma, whatever the
nature of the diet, and even in starving animals.^ It occurs in man to
the amount of about 0'12 per cent, of the blood, in the dog from Oil
to 015 per cent, (or a httle over 1 per 1000).^ It is present in
nearly equal amount in blood from all parts, except in the blood of the
portal vein, during digestion of carbohydrate-containing foods, where
it is markedly increased. In the blood of the hepatic veins, in the
intervals of digestion, the amount was stated by Bernard to be some-
what greater than in the portal vein, or in the blood of the general cir-
culation ; but this difference has not been found by Pavy and most other
observers, although the statement has of late been reaffirmed by Seegen.*^

Bernard '^ obtained a larger amount of sugar from arterial than from
venous blood, and Seegen has in some instances obtained a similar
result. Chauveau,^ and Chauveau and Kaufmann,^ have also published
analyses, which seem to show a disappearance of sugar after passing
the capillaries. But the differences observed have not been constant,
and are in any case so small as to lie within the range of experimental
error. As the result of eleven experiments, Pavy finds the sugar in
arterial blood to exceed that in venous by only 0*003 parts per 1000 ;
and he concludes that no appreciable difference exists between the two.^*^

1 E. A. Schafer, "A Course of Practical Histology," London, 1876, p. 39; Salomon,
Deutsche oned. TVchnschr., Leipzig, 1877, S. 92 and 421 ; Arch. f. Physiol., Leipzig, 1878 ;
Centralhl.f. Physiol., Leipzig u. Wien, 1892, Bd. vi. S. 512; Ehrlich, Ztschr.f. klin. Med.,
Berlin, IS'SS, Bd. vi. S. 40 ; Gabritschewsky, Arch. f. exper. Path. u. Pharmakol., Leipzig,
1891, Bd. xxviii. S. 272; Huppert, OentralU. f. Physiol, Leipzig u. Wien, 1892, No.
14, S. 394 (Huppert found more in dog's blood than in the blood of herbivora) ; Hoppe-
Seyler, Ztsehr.f.'physiol. Chem., Strassburg, 1894, Bd. xviii. S. 144.

- Compt. rend. Acad. d. sc, Paris, 1895, tome cxx. p. 567.

^ Centralhl. f. Physiol., Leipzig u. Wien, 1892, Bd. vi. S. 345.

^ CI. Bernard, Arch. gdn. de m&l., Paris, 1848, tome xviii. p. 303; Pavy, Phil. Trans.,
London, 1860 ; v. Mering, Arch. f. Physiol., Leipzig, 1877, S. 379 ; Otto, Arch. f. d. ges.
Physiol.. Bonn, 1885, Bd. xxxv. S. 467; Pickardt, Ztschr. f. physiol. Chem., Strassburg,
Bd'. xvii'. S. 217; Miura, Ztschr.f. Biol., Miinchen, Bd. xxxii. S. 255.

^ Pavy, "Physiology of the Carbohydrates," 1894, p. 161.

'^ Arch. f. d. ges. Physiol., Bonn, 1884, Bd. xxxiv. S. 388, and 1885, Bd. xxxvii. S.
348; Centralhl. f. Physiol., Leipzig u. Wien, 1893, No. 12; " Zuckerbildung im Thier-
ki-irper," 1890.

■^ Compt. rend. Acad. d. sc. , Paris, tome Ixxxiii. p. 373, and ' ' Lecons sur le Diabete, " 1877.

8 Ibid., 1856, tome xliii. p. 1008.

^ Ibid., 1886, tome ciii. p. 974.

^^ Pavy, Proc. Roy. Soc. London, 1877, vol. xxvi. p. 346 ; "On Certain Points connected
with Diabetes," London, 1878; " Phy.siology of the Carbohydrates," pp. 170-171. This
is also apparently admitted by Seegen ("La Glycogenic Animale," Paris, 1890, p. 100),
although his theory of tlie production of enei'gy requires that there sliould be a diminution
in the amount of sugar in venous blood.



NON-NITROGENO US SUBSTANCES IN PLASMA. 1 59

Apart from these somewhat doubtful differences in blood from different
parts, the amount in tlie blood remains almost constant, whatever the char-
acter of the food, and even during starvation. The amount is somewhat in-
creased as the result of hemorrhage, a result due either to accession of lymph
(which contains a larger proportion of sugar than does blood), or to the
operation, through the agency of the nervous system, causing an increased
production of sugar from the liver-glycogen. If the amount of dextrose in
the blood be artificially increased to more than about 0'25 per cent, the excess
passes off by the urine. The amount is increased in diabetes, whether this be
the result of the sugar puncture, of removal of pancreas, or of disease,^
but even under these circumstances does not rise above 0'48 per cent.

Fats. — These are present in plasma in small but variable quantity
(0'2 to 0-5 or even 1 ]3er cent.)- being most abundant after a meal
containing much fat. The plasma or serum may then be milky from
admixture with the fat-containing chyle. They are composed of the
usual glycerides of fatty acids (palmitin, stearin, and olein). A small
amount, O'05-O'l per cent., is in the form of soap.^ It has been stated^
that there is a greater amount of fat (ether extract) in arterial than in
venous blood, but this result is shown by Eohmann and Miihsam ^ to
have been probably due to an error brought about by venous congestion,



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