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Most of the land which is overgrown with bracken is either rough and stony hill or woodland. In some cases, however, bracken is to be found on good and comparatively level land on which horses and implements could be worked. In such cases it should not be difficult or expensive to harvest the crop of rhizomes. On the other hand, in woodland the trees and their roots seriously interfere with this operation and make it so difficult as to be practically impossible. On rough stony land the difficulty varies according to the nature of the land. On most rough hillsides the crop could only be harvested by laborious hand labour, which would probably render it too expensive to be of any practical use.

In the experiments which I carried out in order to determine the weight of crop per acre, and to obtain a supply of the rhizomes for feeding trials, hand labour was employed. It was found that if the land was cut into squares with spades and turned over, the rhizomes which were thus cut into short lengths, could be easily shaken out with graips and separated quite satisfactorily from the soil and other foreign matters. Although I had no opportunity for trying it, there is little doubt that on land on which tractors or horses and implemens could be used, the crop could be ploughed out, especially if a disc or other suitable cutting implement were attached in front of the plough to cut the rhizomes to a depth of about six inches. The crop could thus be separated from the earth and collected with graips. Possibly in some cases this would be an easier and cheaper method of destroying bracken on infested lands than the

laborious method of repeatedly cutting the fronds over a period of two or more years.

A large number of samples of bracken rhizomes obtained from various parts of Scotland at different times of year were analysed. The composition of a number of these is shown in Table I., and for comparison the average composition of potatoes is given.

The bracken root samples were all collected between May and August. When those obtained from Mugdock Wood were gathered, the fronds had already begun to grow though they were not yet uncurled. These samples were obtained from the locality where a few tons of the rhizomes were dug for the feeding and meal-making experiments which are described below.

Samples were also taken from two different places in rough woodland at Craibstone, the experimental farm of the North of Scotland College of Agriculture. From each of these two places, distinguished in Table II. as "A" and "B," ten samples were taken, distributed systematically throughout the whole year from the beginning of April, 1918, to March, 1919. This was done to test the variation in the composition of bracken rhizomes throughout the year. The complete results of these analyses will be discussed elsewhere, and only the average results of the ten analyses from each place are shown in Table II.

While the figures in Table II. show the average composition for the whole year of rhizomes from the two places chosen, considerable changes in composition were found throughout the year at both places. As might be expected the rhizomes

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became poorer both in albuminoids and in soluble carbohydrates after the growth of the fronds became active in spring. But this fall in quality lasted for two or three months only, after which the rhizomes recovered again, especially in soluble carbohydrates. Further, it is important to notice that at no time were the rhizomes exhaused, or anything like exhausted, of their food stores. Thus in the case of the "A" samples, the albuminoids at the beginning of April, before the fronds had appeared above ground, were 2:09 per cent; this fell by the beginning of June to 10 per cent and by the middle of July to o'44 per cent, but by the middle of August it had risen to 169 per cent, and in the case of the "B" samples the corresponding figures were beginning of April 5:36 per cent, early June 401 per cent, middle of July, 2:01 per cent, middle of August 3:44 per cent. This indicates that the stores of nitrogenous material in the rhizomes are drawn upon for frond formation until July, when the fronds are fully grown, and that after that storage of nitrogenous material in the rhizomes again begins.

Something similar was found in the case of the soluble carbohydrates, except that they were never reduced to nearly so great an extent as the albuminoids, and they began to increase again more quickly. Thus in the case of both the A and B samples they reached their minimum in June, and the percentage was in both cases greater in August than at the beginning of April.

These facts illustrate the necessity of cutting bracken fronds early and repeatedly if the rhizomes are to be exhausted and the plants destroyed. If cutting is delayed till the fronds are fully developed, storage of food materials has already begun again. The longer cutting is delayed after the fronds are fully developed, the more food the plant is able to store in the rhizome. On the other hand, if cutting or breaking down of the fronds is carried out before they are fully developed, the rhizome is very incompletely exhausted of its food stores, and will not have much difficulty in sending up another vigorous crop of fronds. So far as these analyses go, they indicate that the best time to cut bracken is about the middle of July, as at that time the store of nitrogeneous material in the rhizomes is at its lowest, and therefore the next crop of fronds sent up is bound to be much weakened for lack of nitro

geneous matter.

The analyses indicate, on the other hand, that the worst time to obtain bracken rhizomes for use as food is in July, for at that time they are lowest in the valuable food constituents, albuminoids and soluble carbohydrates, and highest in the almost valueless fibre. After July they improve in composition, and are at their best in winter and in spring, when growth is just beginning. After April they deteriorate, but samples raised in April

8.65 2.12 1.86 5708

were as good as those obtained at any time of

year.

It was found that the percentage of albumine:d: varied greatly in different samples of brackes rhizomes. This is very markedly shown by the A and B samples from Craibstone (Table II.. The average of the ten B samples shows more tha three times the albuminoids in the average of the ten A samples. Not only so, but every individual B sample contained a far higher percentage of Ir albuminoids than the corresponding A sample. some cases it was seven times as great.

Some analyses were also made of the frondfrom A and B, and it was found that this peculiarity extended to them also. Fronds grown at B were much more nitrogenous than those grown at A, though the relative difference was not quite So great as in the case of the rhizomes. (To be continued.)

NOTES.

CARNAUBA WAX.-Before the war carnauba wax was an important export from Brazil. Exports: 1916--4167 metric tons; average prices, $4.80; 1917-3669 metric tons; average prices $5.75The chief exporting ports are Fortleza and IlhaCagneiro, and the principal buyers the United States, Great Britain, and France.-Matières Grasses, Nov. 15.

LEMON SEED OIL.-The "pastazzo" or residue from washing citrate of calcium &c., in the manufacture of citric acid contains a large quantity of pips. P. Bertolo considers that this waste product, of no commercial value, could be profitably utilised for oil extracted by pressure or with solvents. By the last method the yield is 30 to 35 per cent, according to the degree of maturity. The oil from the press is light yellow and rather fluid with the odour of lemon and tart in flavour. That extracted with solvents is somewhat turbid and gives a considerable volume of pasty sediment consisting chiefly of solid saponifiable matter. The oil is semi-siccative and resembles cottonseed oil, containig a very high percentage of liqud giv cerides and less than 28 per cent solid.-Giornale Ch. Applicata, 1920.

THE KATOKA TREE.-The commercial interest evinced this year in the edible seeds of the Katoka tree, imported from the West of Madagascar, led M. Jumelle to study the botanical origin of these seeds. The Katoka is an Artocarp which may be regarded as new and belongs to the genus Treculia. It is consequently akin to the Jack tree

nd bread fruit tree. The Katoka is a tree which ay attain a height of 30 metres. Its trunk Aways deeply furrowed, has a smooth grey tinted ark. It gives a large quantity of edible seeds, with a small percentage of oil.-Comptes 'endus, December 8, 1920.

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THE NOLI PALM.-The oil palm of merica is the Elais Melanococca Gaertin. It is -nalogous with the Elais Guineensis of West frica, but is smaller. The flesh of the fruit epresents 16 per cent; the nut 84 per cent, 62 er cent of which is shell. The flesh contains 8.1 er cent water, and 29 per cent of oil, which is quivalent to 315 per cent of oil in the dessicated ruit. The oil is a liquid of an orange yellow olour, with a high percentage of free skarin. It s more fluid and lighter in colour than the West African palm oil. The constants are as follows :

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PORTLAND CEMENT AND CALCIO CYANAMIDE.-The production of ammonia and then consequently of sulphate of ammonia from cyanamide according to the equation CaCN2+3H2=CaCO,+2NH, which already before the war was greatly developed, gives a troublesome residue in form of a blackish slime which when dry turns to a noxious grey powder. According to Julius Baumann (Chemiker Zeitung, July 29) the Velvorde Works, near Brussels, was obliged to cease work because this by-product could not be utilised, and he considers it absolutely necessary to find some means for its utilisation in order to give a greater development to manufacture of ammonia from calcio cyanamide. Baumann considers that the best method is to employ this black slime for manufacture of Portland cement. Experiments were made in which 4'71 parts of dry slime were mixed with 1 of crushed burnt clay in a kiln, at a white heat, until quite soft. Had it been possible to employ a rotary kiln the slime could have been 0.8586 treated without drying. Thus, the possibility of 36°-46° utilising this waste product was fully demonstrated, and will benefit the industry for manufacture of ammonia from calcio cyanamide.— Giornale di Chimica Industriale, Nov., 1920.

W. Africa
Palm Oil.

196-205
53-57

0.7 per cent

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Soluble volatile fatty acids
Insoluble volatile fatty acids
The kernels contain 72 per cent water and 45 4
per cent oil, viz., 487 per cent in the dessicated
seeds; it is a solid pale cream fat.

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W. Africa
Palm Oil

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--

10'3-17'5

5-6.8

10-12

-Matieres Grasses, Nov. 15.

THE FUEL QUESTION IN NORWAY.-According to figures issued by the Central Committee of Norwegian Scientific and Industrial Research, about 3 million tons of coal, coke, and cinder, are imported annually into Norway, this representing 20 per cent of Norway's total imports. During the year 1918-1919, 50,000 tons of coal were mined at Spitzbergen; hopes are being entertained of increasing this amount, but the town's geographical 20°-25°5 position introduces serious transport difficulties. The Norwegian waterfalls are capable of pro242-255 | ducing 15 million kilowatts, of which only 1,200,000 kilowatts are being at present utilised; half of which is used in industry, the other half is used for the running of motors and lighting. If all motors and lighting in Norway were electrified, another 1 million kilowatts would be needed. The 3 million tons of imported fuels are equivalent to 2 million kilowatts, or 2.7 million h.p. It , however, impossible to wholly substitute the use of fuel, for it is indispensable to steamers, in the manufacture of carbide, and for partial househeating during the coldest part of the season. Assuming this quantity of fuel to be 800,000 tons the remaining 22 million tons, equivalent to 2 million h.p. should be obtained by the utilisation of water power. Other sources of fuel are the waste wood of the forests, equivalent to 1.2 million tons of coal. Norway has 12,000 square kilometres of peat land, of which about one-sixth (2000 square kilometres) is adaptable as fuel. Calculated to a depth of 2 metres, the said area will give 600 million tons of peat, equivalent to 300 million tons of coal. The Committee recommends a thorough economy with all fuel. It is suggested that a thoroughly rational firing would save 30 per cent of all the fuel now used in Norway. If we only calculate on a 10 per cent saving, this means 3 million tons of coal, a quantity not at all to be neglected. Much fuel culd be saved in house-heating by more economically constructed stoves and better isolation of walls and windows. The Committee further recommends the appointment of a permanent Fuel Committee, in order to survey the economical firing in industry and households.

SELECTING OIL CAKES.-A paper by M. Ringelmann, read at the French Academy of Agriculture, deals with the selection of oil cakes. The alimentary value of a cake, he observes, is chiefly represented by its proteinous richness, but as it is to the interest of farmers to buy the food-stuff in form of cakes, we must also consider the cost of crushing, which may vary in the ratio of 1 to 5, - according to the hardness of the cakes. According to his experiments, M. Ringelmann considers that the following classification may be made: Soft Cakes--Home-grown colza; Egyptian cotton (first crop); home-grown linseed; sesamum; red copra; cocoanut. Hard Cakes-Shelled peanuts; Egyptian cotton (second crop). Very Hard Cakes Niger and white poppy. This classification, relating to the cakes tested, may certainly vary with oil mills. Briefly, the richness in protein is not a sufficient guide in selection of a cake. Cost of crushing must be estimated, i.e., the mechanical work expended on the operation. An idea can be obtained from comparative tests of cakes, ascertaining with the same machine and regulation the number of revolutions required to crush a certain weight of cakes, with examination of the volume and weight of the screened pieces, because, as far as possible, production of meal or grits must be avoided.-Vie Agricole, Oct. 23, 1920.

324

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THE DUTCH COLOUR INDUSTRY.-The following details are taken from a report published by the Dutch Ministry of Commerce on the colour industry during the first six months of the year. "A good flow of business has been produced in lakes, varnishes, and colours, and there is a satisfactory demand from other countries. The situation is favourably influenced by the activity displayed in the building industries, especially in the devastated districts of the North of France. Dutch imports of colours and lakes were follows. White Lead-573 metric tons, in which 276 were from Germany and 85 from America. Zinc White-1969 metric tons; 1636 being German. Red Lead-525 metric tons. Ochre-565 Other metric tons; 199 French, and 192 German. Coal Tar ColoursColours-1247 metric tons. Crushed 581 metric tons, 456 being German. Colours-278 metric tons. Lakes-52 metric tons; 35 German. Siccatives and Varnishes-102 metric tons; 6 English, and 26 United States. Exports: Zinc White-1062 White Lead-19 metric tons. metric tons; 494 for Belgium. Lithopone--3566 metric tons 2793 for Belgium; 365 for France. Red LeadCrushed Colours-683 metric tons. 105 metric tons. Other Colours-1183 metric tons.

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AN

63, LUDGATE HILL, LONDON, E.C.4.

ad

N old-established small practice in London for sale, suitable well trained young Analyst, or would consider junior partner.-Apply Box 820, c/o SCOTT & SON, 63, Ludgate Hill, E.C.4.

Coal Tar Colours-44 metric tons. Siccatives PATENTS, TRADE MARKS. Handbook

and Varnishes-110 metric tons; 26 for Sweden, 16 Norway, 11 Denmark, 30 Dutch Indies.-Rev. Produits Chimiques, October 15, 1920.

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and advice free-B. T. KING, British and U. S. Regd. Patent Attorney, 146a, Queen Victoria St., London. 35 years reference

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INDEX.

ACETALDEHYDE, emanation
from ripe apples, 129, 139, 147
Acid, acetic, distribution between
water and charcoal, 49
carbonic, dilatation and com-
pressibility of liquid, 248
hydrocyanic, action on glucose,

131

nitric, synthetic, 10

phosphoric, and nitrogen of
wheat, 262

Aeronautical engineering, appli-
cations of electro-deposition
in, 399

Africa, South, associated scien-
tific and technical societies
of, 83
Aggregation at the melting point,
87, 151

Aitchison, Leslie, electroplating
for the prevention of corro-
sion, 309

Alcohol fuel development, 203
fuel patents, 131

Aliphatic compounds, simple

relations between the con-
stitution of, and their sweet
taste, 159

Alkali rocks, origin of, 273

Allen, G. D., service experience
with condensers, 166
Alsace, Upper, potash deposits
of, 142

Alsatian potash, 119
potash salts, 250
Aluminium, 178

and its alloys, plating of, 9
and magnesium alloys, con-
stitution, 154

America, rat extermination for
the United States, 167
Ammonia-soda process, 295
Anglesey, geology of, 11
Aniline stannichloride, quinoline
from, 239
Antimony-copper-tin

alloys,
constitution and structure,

155

Apparatus for collecting samples

of water at great depths, 297
Victor Meyer's, 249, 307
Apples, odorous constituents of,

and emanation of acetalde-
hyde from the ripe fruit,
129, 139, 147
and T. P.
Armstrong, E. F
Hilditch, study of catalytic
actions at solid surfaces, 43

Association of British Chemical | Baumann, Julius, Portland ce-

Manufacturers, 215

Aston, F. W. and T. Kikuchi,

moving striations in neon and
helium, 46
Atmosphere, relationship between
pressure and temperature in
the free, 248

Atomic structure, magnetism and,

272

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ment and calcio cyanamide,
323

Benn, E. J. P., are profits
necessary? 11
Bennett, A. G., occurrence of

diatoms on the skin of whales,

45

Bergengren, Mr., spectra of
absorption of phosphorus for
X rays, 268

Bertolo, P., lemon seed oil, 322
Bingham, Kathleen, E., allotropy
of zinc, 167
Birmingham University, 191

University and research, 202
Bismuth, gravimetric estimation
as phosphate and its applica-
tion in ore analysis, 297
Bloch, Leon and Eugene, spectra

of samples of mercury,
copper, zinc and thallium in
the extreme ultra-violet, 298
Bohemian glass industry, 47
Bonardini, J. P. and Edward P.
Barrett, determination of
molybdenum, 196. 206, 231,

245, 256

Ballard, W. E. and T. G. Bam-Books, Reviews and Notices of-
ford (See Bamford, T. G.)
Bamford, T. G. and W. E.

Ballard, influence of gases on
high-grade brass, 154

Barberry, fruit of the Japanese,
61

Barclay, W. R., electro-silver
plating and its technical
development, 310
Barium, spectrum of, revision of
the series in, 11
Barker, G. and E. Tomkinson
(See Tomkinson, E.)
Barnett, Edward de Barry, modi-

fication of Skraup's quinoline
synthesis, 205

Barr, Guy, new relay for heavy
currents, 287

Barratt, S., origin of the cyanogen
bands, 45
Barratt, T. and A. J. Scott, radia-

tion and convection from
heated surfaces, 8
Barrett, Edward P. and J. P.

Bonardini (See Bonardini,
J. P.)

Barry, Paul, colloidal sulphur,
142

Bateson, William, genetic segre-
gation, 7

"Berzelius, Letters of," 22
"Bygone Beliefs," 46
"Chemistry, Intermediate
Text-book of," 9
"Margarine," 250

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'Oils, Fats and Waxes, Animal
and Vegetable," 58
"Techno- Chemical Receipt
Book," 46

Borates, 194
Bougault, J. and J. Perrier, action
of hydrocyanic acid on glu-
cose, 131
Bourquelot, Emile, glucosane,
107
Bouton, C. M. and L. H.

Duschak, determination of
mercury, 23
Bouvier, Pierre, and Pierre
Jolibois (See Jolibois, P.)
Bracken rhizomes and their food
value, 320

Brackenbury, Cyril, automatic

counting machine for check-
ing tram waggons, 296
Bradford Technical College, 178
Brannerite, 22
Brannt, Wm. T. and Wm. H.
Wahl, "Techno-Chemical
Receipt Book" (Review), 46

the

Brass, beta, features in
behaviour of, when cold-
rolled, 166

foundry practice at Messrs.
Vickers, Limited, 153
influence of gases on high-
grade, 154

British Association, presidential
address, 97, 109

chemical section, presidential
address, 121

engineering section, presiden-
tial address, 171, 188
British chemical glassware, 253
Industries fair, 1921, 143, 155
Brook, G. B., appointment, 48
crystalline structure of electro-
deposited silver, 311
Brook, G. B., and L. W. Holmes,

chemical composition of old
silver-plating solutions, 310
Brotherton's, ammonia distillery,
178

Bucchlans, W., linseed oil sub-
stitutes, 311

Bulgaria, production of attar of

Burgess, George K., temperature
roses in, 52

measurements in steel fur-
naces, 289

Burgess, W. T., apparatus for
collecting samples of water
at great depths, 297
J. F.,
Butterworth,
results
achieved in industry by
modern methods, 70, 77

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