APPENDIX.

Velocity Table.

The following is a tabular form showing the velocities of moving bodies as given by Peschel:

Feet per second.

Rivers3–4

Very rapid stream13

Wind (ordinary)10

Storm54

Hurricane80–120

Sound (through air)1100

Sound (through metal)12,000

Air in vacuum1280

Ball from air-gun Air condensed 100 times 697

Musket ball1280

Rifle ball (at most)1600

Cannon ball (24-pounder)2450

Earth’s rotation (at equator)1525

Earth’s centre in its orbit101,061

Miles per hour.

Racehorse60

Pigeon20–30

Peregrine falcon120

Ocean steamers21

River steamers22

Railway train80

Sailing vessel10

Malay proa20

Miles per second.

Light200,000

Electricity576,000

Weight of a Superficial Foot of Plate or Sheet Iron.

No. of the wire guage. Thickness in inches. Weight in pounds. No. of the wire guage. Thickness in inches. Weight in pounds. No. of the wire guage. Thickness in inches. Weight in pounds.

1 40 5 8·74 18 1·86

⅞ 35 6 8·12 19 1·70

¾30 7 ³⁄₁₆7·5 20 1·54

¹¹⁄₁₆27·5 8 6·86 21 1·40

⅝25 9 6·24 22¹⁄₃₂1·25

⁹⁄₁₆22·5 10 5·62 23 1·12

½20 11⅛5 24 1

⁷⁄₁₆17·5 12 4·38 25 0·9

⅜15 13 3·75 26 0·8

1 ⁵⁄₁₆12·5 14 3·12 27 0·72

2 12 15 2·82 28¹⁄₆₄0·64

3 11 16¹⁄₁₆2·50 29 0·65

4¼10 17 2·18 30 0·50

Weight in Pounds of One Cubic Foot of the following Substances

lbs. lbs.

Cast iron450Water 62·5

Wrought iron486Air 0·075

Steel489Steam 0·036

Pine wood 29·5

Weight of Rod Iron One Foot in Length of the following Dimensions:

Square Iron. Round Iron. Flat Iron.

Inch. Pounds. Inch. Pounds. Inch. Pounds.

¼ 0·2 ¼ 0·14 ¼ × 1 0·8

⅜ 0·5 ⅜ 0·4 ⅜ × 1 1·3

½ 0·8 ½ 0·7 ½ × 1 1·7

⅝ 1·3 ⅝ 1 ⅝ × 1 2·1

¾ 1·9 ¾ 1·5 ¾ × 1 2·5

⅞ 2·6 ⅞ 2 ¼ × 2 1·7

1 3·4 1 2·7 ⅜ × 2 2·5

1⅛ 4·3 1⅛ 3·4 ½ × 2 3·4

1¼ 5·3 1¼ 4·2 ⅝ × 2 4·2

1⅜ 6·4 1⅜ 5 ¾ × 2 5·1

1½ 7·6 1½ 6 ¼ × 3 2·5

1⅝ 8·9 1⅝ 7 ⅜ × 3 3·8

1¾ 10·4 1¾ 8·1 ½ × 3 5·1

1⅞ 11·9 1⅞ 9·3 ⅝ × 3 6·3

2 13·5 2 10·6 ¾ × 3 7·6

2¼ 17·1 2½ 13·5 ¼ × 4 3·4

2½ 21·1 2½ 16·7 ⅜ × 4 5·1

2¾ 25·6 2¾ 20·1 ½ × 4 6·8

3 30·4 3 23·9 ⅝ × 4 8·4

3½ 41·4 3½ 32·5 ¾ × 4 10·1

4 54·1 4 42·5 ¼ × 5 4·2

5 84·5 5 66·8 ⅜ × 5 6·3

6 121·7 6 95·6 ½ × 5 8·4

7 165·6 7 130 ⅝ × 5 10·6

8 216·3 8 169·9 ¾ × 5 12·7

Relative Heat-conducting Power of different Bodies.

Gold 1000 Fire brick 11

Platinum 981 Fire clay 11.4

Silver 973 With Water as a Standard.

Copper 898 Water 10

Iron 574 Pine 39

Zinc 363 Lime 39

Tin 304 Oak 33

Lead 180 Ash 31

Marble 24 Apple 28

Porcelain 12·2 Ebony 22

Relative Conducting Power of different Substances compared with each other.

Hare’s fur 1·315Cotton 1·046

Eider down 1·305Lint 1·032

Beaver’s fur 1·296Charcoal ·937

Raw silk 1·284Ashes (wood) ·927

Wool 1·118Sewing silk ·917

Lamp black 1·117Air·576

Relative Conducting Power of Fluids.

Mercury1·000Proof spirit·312

Water·357Alcohol (pure)·232

Radiating Power of different Bodies.

Water100Blackened tin100

Lamp black100Clean tin12

Writing paper100Scraped tin16

Glass90Ice85

Indian ink88Mercury20

Bright lead19Polished iron15

Silver12Copper12

The Stone Weight.

The term “stone” is often used to indicate weight, but some confusion is apt to arise if the nature of the object or substance to be weighed is not clearly indicated; thus, in weighing men according to what is known as “horseman’s weight,” 14lb. avoirdupois are made use of; in weighing butcher’s meat, 8lb.; iron, 14lb.; glass, 5lb.; hemp, 32lb.; cheese, 16lb.

The Qualities of Gold.

Very few terms are more loosely used than that of “gold,” and it is therefore necessary that the traveller should make himself fully acquainted with the nature of the alloy made use of under the name of gold in the various countries he may chance to visit. Let him not suppose that, because the glittering chain or ring displayed in an English jeweller’s window is marked in conspicuous letters “Warranted fine gold,” the ornament is as a matter of course composed of pure gold, or he will buy experience dearly. Fine gold means nothing further than that an alloy of some kind containing some gold is for sale. It is well, therefore, to insist on the exact quality of the article (in carats—18 carats, 22 carats, or whatever it is represented to be) being stated on the vendor’s bill of charge.

The nature of gold alloy differs materially in various countries. We have, therefore, thought it well to provide the reader with the following useful tables compiled by Mr. E. W. Streeter and used in his “Hints to Purchasers of Jewellery.”

Qualities of Gold manufactured in different Parts of the World.

£ s. d. £ s. d.

England From 1 carat, worth 03 6 to 22 carats, worth 3 17 10½

France ” 18 carat, 33 8½ only common by special permission.

Denmark ” 18 ” ” 33 8½

Baden ” 14 ” ” 29 6½

Germany (all States) ” 12 ” ” 22 5½ to 15 carats, worth 2 13 1

Russia ” 15 ” ” 213 1 to 22 ” ” 3 17 10½

Austria ” 10 ” ” 115 4¼ to 18 ” ” 3 3 8½

Italy ” 12 ” ” 22 5½ to 22 ” ” 3 17 10½

Holland ” 4 ” ” 014 2 to 22 ” ” 3 17 10½

Africa ” 23 ” ” 43 1½

India ” 4 ” ” 317 10½ to 23½ ” ” 4 3 1½

Rome All 18 ” ” 33 8½

U. States of America From 1 ” ” 03 6 to 18 ” ” 3 3 8½

Norway and Sweden All 18 ” ” 33 8½

Belgium From 18 ” ” 33 8½ to 22 ” ” 3 17 10½

Spain All 18 ” ” 33 8½

Switzerland All 18 ” ” 33 8½

Geneva From 14 carat, 29 6½ Watch cases only.

China From 16 ” ” 216 7½ to 23¾ carats, worth 4 4 0

Japan From 18 ” ” 33 8½ to 23¾ ” ” 4 4 0

Brazil All 18 carat, 33 8½

Hamburg From 13½ ” ” 211 3½ to 18 ” ” 3 3 8½

Turkey ” 18 carat, 33 8½

Greece ” 10 ” ” 115 4¼ to 16 ” ” 2 16 7½

Persia ” 3 ” ” 010 7½ to 23½ ” ” 4 3 1½

Egypt ” 18 carat, 33 8½

Rio Janeiro Imported from 1 carat 03 6 to 22 ” ” 3 17 10½

Chili ” ” 03 6 to 22 ” ” 3 17 10½

Peru ” ” 03 6 to 22 ” ” 3 17 10½

Siam Nearly pure, fine work.

Australia Same as England, except that made up from the diggings.

Mexico Principal manufacture fine.

Any quality is allowed to be imported into these countries.

The following table by the same author will serve to show in a condensed form, the value of different gold alloys relatively, and also the extremely low standard at which so called “gold articles” are manufactured in this country.

Gold Value Table.

£s.d.

22-carat gold is worth31710½per oz.

18” ”338½”

16” ”2167½”

14” ”296½”

10” ”1154¼”

9” ”11110 ”

8” ”183¾”

6” ”112½”

4” ”0142 ”

2” ”071 ”

1” ”036 ”

Since writing the early portion of this work, we have found it requisite, in order to supply a manifest want, to have manufactured a small leather case (on the exact model of our own), containing all the tests and appliances requisite for the identification of precious metals or precious stones.[D]

We have also caused to be constructed, from our own pattern, a small triple branch of gold of different degrees of alloy. Each branch, when rubbed on the touch stone, and treated with nitric acid, will leave a characteristic streak, which may be compared with one formed by rubbing the article to be tested, and treating it with acid in the same manner; the nature of the alloy will thus be found by comparison.[E]

Emerson’s Table of Strengths, showing the Load that can be safely borne by a square inch Rod of each of the following Substances:

lbs. avoir.

Iron rod, 1in. square, will bear 76,400

Brass 35,600

Ivory 15,700

Oak, box, yew, plum-tree 7,850

Elm, ash, beech 6,070

Walnut, red fir, holly, elder, plane, crab 5,000

Cherry, hazel 4,760

Alder, asp, birch, willow 5,000

Lead 430

Freestone 914

Emerson’s rule is, that a cylinder, the diameter of which is d inches, loaded to one fourth of its absolute strength, will carry as follows:

cwt.

Iron135 × d²

Good rope22 × d²

Oak14 × d²

Fir9 × d²

Another of his rules is that a cylindrical rod of well-seasoned clean-grown fir of an inch circumference drawn in length will bear at its extremity 400lbs. and a spar of fir 2in. in diameter will bear about 7 tons, but not more. A well-made and carefully-kept hemp rope of one inch in circumference, will bear 1000lbs. being at its extremity.

Mr. Barlow has formed the following table as a mean resulting from experiments on the strength of direct cohesion on a square inch of the following substances:

lbs.

Box 20,000

Ash 17,000

Teak 15,000

Fir 12,000

Beech 11,500

Oak 10,000

Pear 9,800

Mahogany 8,000

He also states as follows regarding the transverse strength of beams, &c. Mr. Weale thus quotes from Mr. Barlow’s essay: “The transverse strength of rectangular beams, or the resistance which they offer to fracture, is as the breadth and square of the depth; therefore, if two rectangular beams have the same depth, their strengths are to each other as their breadths, but if their breadths are the same, then their strengths are to each other as the square of their depths. The transverse strengths of square beams are as the cubes of the breadths or depths. Also in cylindrical beams the transverse strengths are as the cubes of the diameters. Thus, if a beam which is one foot broad and one foot deep support a given weight, then a beam of the same depth and two feet broad will support double the weight; but if a beam be one foot broad and two feet deep it will support four times as much as a beam one foot broad and one foot deep. If a beam one foot square support a given weight, then a beam two feet square will support eight times as much. Also a cylinder of two inches in diameter will support eight times as much as a cylinder one inch in diameter. The appended table gives data bearing on the subject.

Teak 2·462Elm 1·013

English oak 1·672Pitch pine 1·632

Canadian oak 1·766Red pine 1·341

Dantzic oak 1·457New England fir 1·102

Adriatic 1·383Riga fir 1·108

Ash 2·026Mar Forest fir 1·262

Beech 1·556Larch 1·127