Louis Edgar Andés.

Animal fats and oils, their practical production, purification and uses for a great variety of purposes, their properties, falsification and examination; a handbook for manufacturers of oil- and fat-products, soap and candle makers, agriculturists, tanners, etc., etc online

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Online LibraryLouis Edgar AndésAnimal fats and oils, their practical production, purification and uses for a great variety of purposes, their properties, falsification and examination; a handbook for manufacturers of oil- and fat-products, soap and candle makers, agriculturists, tanners, etc., etc → online text (page 1 of 23)
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LIBRARY

OF THE *

UNIVERSITY OF CALIFORNIA.



Cla&s



ANIMAL FATS AND OILS



ABERDEEN UNIVERSITY PRESS



ANIMAL FATS AND OILS

THEIR PRACTICAL PRODUCTION, PURIFICATION

AND USES FOR A GREAT VARIETY OF PURPOSES

THEIR PROPERTIES, FALSIFICATION AND

EXAMINATION

A HANDBOOK

FOR

MANUFACTURERS OF OIL- AND FAT-PRODUCTS, SOAP
AND CANDLE MAKERS, AGRICULTURISTS,

TANNERS, ETC., ETC.



LOUIS EDGAR ANDES



WITH 62 ILLUSTRATIONS



TRANSLATED BY

CHARLES SALTEE




LONDON
SCOTT, GKEENWOOD & CO.

PUBLISHERS OF THE



19, 21, AND 23 LUDGATE HILL, E.C.
1898



GENERM-



PREFACE.

As in the case of Vegetable Fats and Oils, consider-
able improvements have been introduced into the
preparation of the animal products belonging to
the same category ; and, whilst for the most part
relating to mechanical methods, have given this
industry a marked impetus.

Now-a-days the preparation of tallow and hog
fat is conducted in a rational manner, and the manu-
facture of that valuable food-stuff butter is carried
on according to methods calculated to thoroughly
utilise the raw material milk and to yield a pro-
duct endowed with a better flavour than under the
primitive conditions formerly prevailing. Improve-
ments have also been made in the preparation of
bone fat, waste fat, fish oils, etc., all of which I
have thought it advisable to include in the present
work in order to render it more acceptable to those
interested in the fat industry.

LOUIS EDGAR ANDES.



121034



TABLE OF CONTENTS.



Introduction ]

Occurrence, Origin, Properties and Chemical Constitution of

Animal Fats 6

Preparation of Animal Fats and Oils 20

Machinery for Breaking down Fat 23

Pans and Apparatus for Fat Melting 26

Toncou's Tallow-Melting Plant 28

Tallow-Melting Plant for Sulphuric Acid Method ... 30

Wilson's Tallow-Melting Apparatus 32

Gellhorn, Flottmann & Co.'s Tallow-Melting Apparatus . . 33

Lockwood & Everitt's Tallow-Melting Apparatus ... 38

Steam Apparatus for Tallow Melting 40

Rivoir's Steam Apparatus for Tallow Melting . . < . 42

O. Heintschel's Tallow Melting, etc 44

Fat-Extracting Apparatus with Corrugated Bottom ... 49

Extraction Plant 51

Dr. Ahrens' Apparatus for Extracting Bone Fat ... 52

Kaleczok's Bone-Fat Extracting Apparatus .... 57

Holdhaus' Apparatus for Extracting Fat 58

Meikle's Apparatus for Extracting Bones, etc 59

Machalski's Apparatus for Extracting Fat and Glue . . 61

Schweitzer's Extraction Plant 62

W. O. Robbin's Extractor 63

Perfected Extraction Apparatus 64

Presses 66

Hydraulic Presses 66

Hydraulic Tub Presses 68

Brinck & Hiibner's Hydraulic Presses 69

Simple Presses 72

Fish Oil Screw Press 73

Filtering Apparatus .74

Animal Fats and Oils: Raw Materials, Preparation, Properties

and Uses 75

Alligator and Crocodile Oil 75

Butter : Raw Material and Preparation . . ; . . 76

Properties 89



Vlll TABLE OF CONTENTS.

PAGE

Adulterations .92

Beef Lard or Re-Melted Butter 93

Testing 95

Candle-Fish Oil .......... 105

Mutton Tallow 106

Hare Fat 108

Goose Fat . 108

NeatsfootOil 108

Bone Fat .... . Ill

Bone Boiling 114

Steaming Bones 116

Extraction 120

Refining v . 122

Bone Oil 124

Artificial Butter: Oleomargarine 125

Margarine Manufacture in France .125

Grasso's Process 128

" Kaiser Butter " 130

Jahr and Miinzberg's Method . 131

Filbert's Process . . . . - . . . . . .132

Winter's Method 132

Human Fat 132

Horse Fat . .135

Beef Marrow . . 136

Turtle Oil 136

Hog's Lard : Raw Material ...... . 137

Preparation 138

Properties 139

Adulterations 141

Examination 141

Lard Oil . .149

Tallow : Beef Tallow : Raw Material 150

Preparation 151

Melting in Open Pans (Rendering) 152

Melting with Caustic Soda 157

Melting with Sulphuric Acid 157

Stein's Tallow-Melting Process . 158

Rovard's Tallow-Melting Process 159

Melting by Steam . 160

Properties . . 160

Adulterations 163

Examination 164

Determination of Value 166



TABLE OF CONTENTS.



Detecting Adulterations . . . ..... 16 ^

Kefining, Hardening and Bleaching ...... 171

Animal Oil : Dippel's Oil ......... 176

Fish Oils ............ 177

Whale Oil ........... 181

Porpoise Oil : Brown Fish Oil ......

Dolphin Oil ........... 182

Sperm Oil ........... 18S

Arctic Sperm Oil .......... 183

Finback Whale Oil ......... 184

Greenland Whale Oil ......... 184

Seal Oils ............ 185

Walrus Oil : Seal Oil ......... 187

Archangel Seal Oil ......... 187

Greenland Seal Oil ......... 187

Greenland "Three Crown "Oil ....... 187

Swedish " Three Crown "Oil ....... 188

Newfoundland Seal Oil ........ 188

South Sea Seal Oil ......... 188

Caspian Seal Oil .... ..... 188

Fish (Waste Train) Oil ...... . . 189

Liver Oils .... ........ 190

Properties .......... .193

Coal-Fish Oil ...... .... 194

Shark's-Liver Oil ....... . 194

Kay-Liver Oil .......... 194

Testing Fish Oils .......... 198

Artificial Train Oil .......... 202

D6gras : Tanner's Grease ......... 204

Examination of Degras ........ 207

Preparation from Fish Oil ........ 211

Degras according to Herrburger ...... 213

Preparation of Commercial Degras ...... 213

Wiener on Degras ......... 215

Olein Degras ........... 216

Degras from Waste Fat ........ 217

Black Degras ........... 218

Wool Fat ............ 218

Properties ........... 220

Purified Wool Fat . ..... 221

Spermaceti .......... . 223

Examination of Fats and Oils in General . . . . 226

Index ............ 233

b



ILLUSTRATIONS.

PIG. FAGB

1. Edge Runners 22

2. Fat-Grinding Mill 23

3 and 4. Fat-Cutting Machine 24, 25

5. Portable Melting Stove .26

6. Fixed Pan for Direct Fire Heat 27

7. Tallow-Melting Plant 28

8. Tallow-Melting Plant 29

9. Melting Pan. (Vertical Section) 30

10. Tallow-Melting Plant with Direct Fire 31

11. Wilson's Tallow-Melting Apparatus 33

12. Gellhorn, Flottmann & Co.'s Tallow-Melting Plant. (Ground

Plan) .34

13. Gellhorn, Flottmann & Co.'s Plant. (Section through Boiling

House) 35

14. Steam Plant for Tallow Melting 39

15. Steamer for Melting Tallow 41

16. Steam Apparatus for Tallow Melting (Rivoir) . . .'42

17. HeintschePs Tallow-Melting Apparatus. (Front Vertical

Section) 45

18. Heintschel's Apparatus. Details of Melting Pan ... 46

19. Heintschel's Apparatus. (Lateral Section) . . . .47

20. Heintschel's Apparatus. (Filtering Cylinder) ... 48

21. 22. Fat-Extracting Apparatus with Corrugated Bottom . 49

23. Fat-Extracting Apparatus with Corrugated Bottom. (Front

View) 50

24. Fat-Extracting Apparatus. Arrangement of Funnel . . 50

25. Ahrens' Bone-Fat Extractor. (Cross Section) . . .53

26. Ahrens' Bone-Fat Extractor. (Cooler) 54

27. Kaleczok's Bone-Fat Extracting Apparatus .... 57

28. Holdhaus' Fat-Extracting Apparatus 58

29. Meikle's Bone-Fat Extractor 60

30. Machalski's Fat and Glue Extractor 61

31. Schweitzer's Extractor . . 62

32. Robbin's Extractor . .63

33. Apparatus for Recovering Fat and Glue 64



Xll ILLUSTRATIONS.

FIG- PAGE

34, 35. Hydraulic Tub Press 68

36. Brinck & Hiibner's Hydraulic King Press .... 70

37. Brinck & Hiibner's Hydraulic Box Press .... 71

38. Hydraulic Margarine Press 72

39. Fish Oil Screw Press .73

40. Filter Press 74

41. De Laval Separator. (Elevation) 79

42. De Laval Separator. (Section) 80

43. Fesca's Centrifuge .81

44. Rennes' Butter Machine 83

45. Brochardt's Butter Machine 84

46. Bergedorfer Cremometer ' 87

47. Zeiss' Butyro-Refractometer 98

48. Killing's Viscosimeter 102

49a. Bone Crusher. (Section) 112

496. Bone Crusher. (Viewed from above) 113

50. Bone-Boiling Pan 114

51. Perforated Vessel for Bones 115

52. Bone Steamer . 117

53. Friedberg's Bone Steamer .120

54. Butter and Churning Machine 127

55. Margarine Worker 128

56. Butter Mill with Fluted Rollers . . . . . .129

57. Moulding Machine for Margarine 130

58. Greaves Press 153

59. Greaves Press 154

60. Greaves Press 155

61. Degras Pan 215

62. Westphal Balance 227




ANIMAL FATS AND OILS.

INTRODUCTION.

THE products known under the name of " animal fats "
are closely related, in respect of both chemical and physical
properties, to the vegetable fats. Like these latter, they are,
almost exclusively, compounds of one, or frequently several,
fatty acids with glycerine ethers ; are, at ordinary tempera-
tures, either solid, semi-fluid or perfectly liquid ; leave be-
hind permanent fatty marks on paper ; dissolve in boiling
alcohol and other liquids ; can be mixed together when in a
melted condition, i.e., in the warm, and are all lighter than
water, so that they float in that liquid. When rubbed in
thin layers on other substances, such, for example, as the
skin, wood, etc., they repel watery liquids, and thereb}^ afford
a certain amount of protection against the penetration of
same. Finally, they exhibit what is generally denoted a
" greasy feel " w r hen handled.

The fats are encountered throughout the animal kingdom,
in all its classes and subdivisions. They are met with
both in mammals, birds, amphibia, fishe,s, and even in in-
sects, and occur particularly in separate layers under the
skin, interspersed in the flesh, between the intestines, or
stored in the brain ; and a great part of the nutriment ab-
sorbed into the animal economy is converted into fat.
Under certain circumstances the fat accumulated in the

animal body will serve to support the individual, for a short

1



% ANIMAL FATS AND OILS.

time, as a means for the continuance of life during periods
when the supply of nutriment is either reduced or entirely
suspended. This is observed in the case of animals (e.g. y
bats, bears, hedgehogs, etc.) that lie dormant through the
winter (hibernate) and awake in spring (or in a favourable
season) reduced in flesh.

The amount of fat stored up in the animal body is a
particularly variable quantity and depends on the supply of
food, mode of life and other circumstances. As a rule, the
accumulation of fat is favoured by a secure and undisturbed
existence, but may also be considerably increased by arti-
ficial means, as we shall see later on. The different ani-
mals turned to account for their fat are comparatively few
in number, and comprise in fact only those that are bred on
a large scale to be utilised partly for food and partly for
technical purposes. Moreover, the fat of many animals is
uneatable, being of unpleasant odour and flavour ; and in the
case of many others it is not present in sufficient quantity to
serve our purpose.

There can be no doubt that the fat of animals, equally
with their flesh, was employed by man, even in the earliest
times, for manifold purposes, originally, however, for food
alone. The use of fat for curative purposes value in which
respect is still attributed to bear's grease, badger fat and
dog's fat by country folk came later. Burning fats for the
purpose of illumination, their use for application to the body
to enable it to better withstand inclement weather, as also for
impregnating clothing and other articles in order to make them
soft, supple and waterproof probably formed the next stage
of extension ; and, finally, in recent times only, their techni-
cal utilisation was developed.

As regards curative powers, the only fat at present play-
ing an important part in this respect is cod-liver oil scarcely
any one now-a-days believes that bear's grease and other fats



INTRODUCTION. <>

have any healing powers, and the substance sold under this
name is merely lard and tallow.

As progress developed in chemico-technical matters, and
as the population increased, attention was naturally directed
towards the recovery and utilisation of fats, and we can see
by the enormous consumption of soap, candles, etc., the
great importance attaching to the production of animal fats
in the present age. Moreover, the bye-products obtained in
the working up of fat play an important role, and this is
particularly the case with glycerine, which is now produced
in enormous quantities. Whereas half a century ago the
glycerine formed during saponification and left behind in the
sub-lye was simply allowed to run to waste along with the
lye, it is to-day a highly important article of commerce, the
amount annually produced throughout the globe being some
40,000 tons not altogether, it is true, from animal fat, but,
from vegetable fats as well. Of this quantity about 26,000^
tons are produced in the manufacture of stearine and 14,000
tons in soap-making.

The preparation of fish oils the best qualities of which
are used as cod-liver oil for medicinal purposes, whilst the
inferior grades are only used for technical purposes, serving
as emollients in leather dressing has also greatly increased '
in extent, although the industry has not, of course, assumed 1
the same importance as that of the other animal fats.

So far as the method of preparing animal fats is con-
cerned, this was until comparatively recently of a very primi-
tive description : the crude fat was melted or " rendered '*
in open pans heated by direct fire either with or without
water, perhaps then melted again for purification, and after-
wards put on the market. The unpleasant exhalations
attendant on some fat-rendering operations, especially when
old fats (partly intermixed with putrescent flesh), bones, etc.,
were being treated, and which contaminated the atmosphere



4 ANIMAL FATS AND OILS.

of all the neighbourhood round such tallow-boiling estab-
lishments, finally led the authorities to insist on a modifica-
tion of the arrangements, so that at the present time fat-
melting works with their perfected appliances carry on their
occupation without producing any smell and without incon-
venience to the vicinity. In recovering fat from bones, glue
as well as fat is produced, the raw material being thereby
fully utilised in a rational manner.

The importance attained by animal fats in the world's
commerce can be gathered from the subjoined statistics,
though the figures will certainly have already been exceeded
since the dates mentioned.

Fish oil annually produced. Spermaceti and Sperm Oil,
1,485,000 hectolitres (of 22 gallons) ; other kinds, 1,170,000 hi.
Oil from sea fowl, 58,500 hi.

The amounts of train and fish oils imported into England
were :

1888. 1889. 1890.

Tons 16,861 21,051 20,302

Value - - - 323,579 442,699 419,926

Exports from the United States :

1889. 1890.

Gallons 483,208 1,844,041

Value 127,412 $440,773

German imports and exports :

1890. 1891.

Imports - 142,668 124,008

Exports 1,948 1,871

Liver Oil. Newfoundland produces annually 1,250,000
galls., valued at 200,000 ; Norway exported (in 1877)
130,600 barrels, of a value of '336,600 ; Norway and Sweden
in 1879, 143,165 hi. (about 3,150,000 galls.).

Spermaceti and Sperm Oil. America produced in 1878
1,300,959 galls. ; 1879, 1,285,454 galls. The exports of sperm
oil from New York amounted to 912,603 galls, in 1878 and
1,089,137 galls, in 1879. This trade has somewhat fallen off



INTRODUCTION. 5

in recent years ; in 1889 the exports amounted to 98,823
galls., worth 869,628, and in 1890 162,565 galls., value
$124,601.

Solid Spermaceti exported from the U.S.A. :

1888. 1890.

Lbs. 425,479 447,384

Value - - .... 11,386 $116,757 (?)

Lard and Lard Oil. The United States produced :

1884-85. 1885-86. 1886-87.

Lbs. - - - 480,405,000 514,230,000 527,032,000

1887-88. 1888-89. 1889-90.

Lbs. - - - 487,179,000 483,902,000 624,227,004

One-third to one-half the above is "compound lard"
(lard mixed with cotton-seed oil and beef stearine). The pro-
duction of this " compound lard " rose to 300,000,000 Ibs.,
but receded in 1890 to 225,000,000 Ibs.

Lard exported from the U.S.A. :

1886. 1887. 1888. 1889. 1890.
Lbs. - 231,509,570 321,523,746(?) 270,245,146 318,242,990 471,083,598
Value - 22,523,197 22,703,921 23,516,097 27,329,173 33,455,520

One-third of the exports come to Great Britain and Ire-
land.

German imports and exports of Lard :

1890. 1891.

Imports 910,277 875,343

Exports 1,364 . 1,484

Tallow. Total production in Europe (1882), 355,700
tons ; U.S.A., 330,000 tons ; other countries, 60,000 tons ;
total 745,700 tons. The exports of Kussian tallow have
considerably diminished of late years ; in 1860 they totalled
40,300 tons ; 1870, 21,100 tons ; 1880, 10,400 tons. On the
other hand, the exports from the U.S.A., Australia and, in a
smaller degree, from South America have increased. In
1883 the exports were: U.S.A., 45,000; Australia, 28,000;
Argentina, 10,500 ; Uruguay, 12,000 tons.



6 ANIMAL FATS AND OILS.

Exports from the U.S.A. :

1886. 1887. 1888. 1889. 1890.

Lbs. - 52,699,115 84,099,951 75,470,826 77,844,555 112,745,370

Value - $2,435,349 $3,772,837 $3,736,488 $3,942,024 $5,242,158

German imports and exports in metercentners (of 2
cwt.) :

1888. 1889. 1890. . 1891.

Imports - - - 62,263 118,126 132,232 108,133

Exports - - - 12,047 5,154 5,925 6,812



OCCUEEENCE, OEIGIN, PEOPEETIES AND
CHEMICAL CONSTITUTION OF ANIMAL FATS.

Fat is found in all the organs constituting the animal
organism and in individual places accumulated in large
quantity as well as in all animal fluids, with the exception
of urine. Certain animals exhibit a greater tendency to
secrete fat than others, the domestic animals having this
faculty particularly well developed. In the animal organism
fat is generally found enclosed in special cells, in larger amount
in connective tissue, in the panniculus adiposus under the
skin, in the plexus of the abdominal cavity, in the vicinity of
the kidneys, in the marrow of the bones and spine, in the
brain, in the liver and in the milk ; occurring pathologically
in so-called fatty tumours and in fatty degeneration of the
various tissues.

Concerning the origin of the fat in the animal body the
following may be asserted : The fat stored up in the bodies
of animals fed on a generous diet does not consist solely of
ready-formed fat absorbed from the food, but is to a consider-
able extent elaborated in the body from other chemical
compounds. From an exhaustive study of the composition
of the nutriment of the herbivorous animals, coupled with a
knowledge of the remarkable changes undergone by organic
bodies outside the organism and reflection on the importance



OCCUEEENCE, OEIGIN, ETC., OF ANIMAL FATS. 7

of the individual constituents of nutrition, Liebig was led to
believe that the carbohydrates (starch, dextrin, sugar) played
an important part in the formation of fat within the body ;
and on the basis of his assumptions the opinion prevailed
during several decades that the formation of fat from carbo-
hydrates was an unassailable fact. In proof hereof were
specially advanced the facts that in the carnivora which,
apart from fat, consume no non-nitrogenous food, the elabo-
ration of fat is generally deficient but increases considerably
when they are placed on a mixed diet with an excess of
carbohydrates ; that the bulk of the food of herbivorous
animals consists of carbohydrates ; and finally, that bees
when fed for a long time solely on wax-free honey or sugar
are still able to produce wax i.e., a fatty body without loss
of health or weight.

Recent researches made by Voigt and Pettenkofer, how-
ever, have made it seem very probable that the albuminoid
substances in the food are, apart from the ready-formed fats
therein, the chief source of fat, and that quite a different
interpretation must be put on the indubitable functions
discharged by the carbohydrates in this connection ; the
latter do not represent the special material from which the
fat stored in the body is produced direct, but are none
the less essential, in the dietary of the herbivorous animals
at least, in order that fat may be elaborated.

Pettenkofer and Voigt have demonstrated that in both
carnivorous and herbivorous animals the decomposition of
albuminoid substances invariably results in the separation
of fat which in the course of further substantive alterations
is either completely consumed, or else, when protected from
further oxidation by the presence of other easily oxidisable
substances like the carbohydrates, remains as a residue in
the body and is laid up therein as a valuable store of reserve
force to be drawn upon in time of need. The importance



8 ANIMAL FATS AND OILS.

of the carbohydrates in the formation of fat is therefore
restricted to preventing the combustion of the fat separated
in the decomposition of the albuminoids, so that the fat has
the opportunity of accumulating within the tissues. Actually,
the fat and albuminoid matters of the dietary are always
sufficient, even in the case of the enormous fat production
exhibited by milch kine, to yield the fat formed, and fatten-
ing with carbohydrates is only efficient provided albuminoids
be simultaneously supplied.

By means of a methodic system of dieting (" fattening"
or " feeding") an increase of the fat and flesh of animals
destined for the slaughter-house can be produced. As the
body fills up in the course of fattening the animal assumes a
condition of imperfect health, for which reason highly justifi-
able objections have been raised against over fattening (a
course of feeding first practised in England) not only from
a medical standpoint but also in view of the utilisation
of the meat. The most nutritious and best flavoured
meat is only obtainable from animals in a condition ranging
from incipient fattening up to the half-fat stage, whilst very
fat beasts, on the other hand, yield chiefly tallow and fat,
but their flesh and blood are deficient in the constituents
acting most effectually on the transfer of matter in the
animal economy.

The following animals are those whose fat is most prized
and utilised : Oxen, sheep, pigs and horses ; among birds the
goose almost exclusively; and also the large marine mammals,
such as the whale and seal, the dolphin, merlangus, shark,
and a number of smaller fishes, such as the cod, ray, herring,
sprat, sardine, anchovy, etc.

The storage places of fat in the animal body are various.
It is often encountered in considerable masses directly under
the skin (as in the pig) or between the intestines (belly fat),
in the brain (in the sperm whale), in the liver (of numerous



OCCURRENCE, ORIGIN, ETC., OF ANIMAL FATS. 9

fishes) ; or, finally, distributed throughout the whole body,
so that in order to recover it the entire carcase must be boiled
or pressed (small fish, such as the anchovy, etc.).

At ordinary temperatures the animal fats when in a pure
state are solid or liquid ; the colour ranges from white to
yellowish- white, pale yellow or brown (fish oils). The solid
fats melt at between 20 and 45 C., and the liquid fats
become semi-fluid or quite firm at temperatures from 5 C.
downwards. The boiling-points are various, and when
heated still further all the fats are decomposed, their glyce-
rine being converted into acrolein, a substance with a most
unpleasant smell. The specific gravity of the animal fats
is lower than that of water and can, as in the case of the
vegetable fats, be regarded as a characteristic indication of
their purity.

When fresh, the animal fats, for the most part, have an
agreeable odour, the only exceptions being sundry fish oils ;
on the other hand, when old, they have generally a rancid
and unpleasant, sometimes putrescent and even repulsive,
smell (old bone fat, blubber, etc.). The flavour of some, i.e.,
those generally employed for alimental purposes (butter,
goose fat, lard), is agreeable ; in others (tallow, especially
mutton tallow), unpleasant ; and in the case of fish oils,
occasionally nauseous. Nearly all fats will produce, even at
the ordinary temperature, grease spots which do not disap-
pear on warming, and even those of highest melting-point
give rise to grease spots when heated. When absorbed by a
wick, all fats will burn with a more or less illuminating,
smoky and strong-smelling flame.

The solid fats when viewed under the microscope at the
ordinary temperature appear throughout as a mixture of
solid and liquid substances. The solid portion consists
mainly of crystals in the shape of plates, needles or tufts,
which are composed of free fatty acids. If the fat be warmed



10 ANIMAL FATS AND OILS.

on a glass slip up to the melting-point, sundry solid amor-
phous granules will still generally be left behind in the mass.

On cooling, the fatty acids crystallise out again, mostly
in the form of needles. In fats poor in olein the liquid
portion appears in the form of drops, but forms the fluid


1 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Online LibraryLouis Edgar AndésAnimal fats and oils, their practical production, purification and uses for a great variety of purposes, their properties, falsification and examination; a handbook for manufacturers of oil- and fat-products, soap and candle makers, agriculturists, tanners, etc., etc → online text (page 1 of 23)