None
1— 1 i 1 1 0.-3 (M 00 th ■* o (M i-H oo I-H t^^ CO o S S • lO -* (N °2 fe P n CO eo CO CO CO rman Wii d 00 o 00 8 00 (DU Cf 00 o o ■** Oi I-H 1 1 1 s o lo ■* ^^ 00 c- Platinum- Silver, the Alloy com- lonly used i Resistance Coils. Ag = 66 %. Pt = 33 %. (M rH o CO Q. QO CO I-H !>► CD CD CD CD GO CM (N (N (>J <N 00 d o °S r— 1 o 00 8 (M 00 s ■*o Oi 1 1 1 PHYSICAL UNITS. 131 Table XVI. Specific Resistance (p) of Carbon at Various Temperatures in 10~° ohm per cubic centimetre (Dewar and Fleming, Phil. Mag., October, 1892). Carbon Carbon Carbon (adaman- from an from an tine) from Edison- Edison- a Wood- Swan Swan house and Incan- Incan- Rawson Remarks regarding Tempe- descence descence Incan- rature. Lamp. Lamp. descence Lamp. !!°C. P- f C. P- t°C. P- 99 3835 O 100 6168 Temperature of boiling water. 18-9 4049 18-9 3911 18-9 6303 „ „ air. 1 4090 1 3953 0-8 6360 „ „ melting ice. -80 4189 -80 4054 -80 6495 „ melting carbonic acid. -100 4218 -100 4079 -100 6533 ,, boiling ethylene. -182 4321 -182 4180 — >, oxygen. 132 PHYSICAL UNITS. Table XVII. Specific Eesistance (approximate) of Liquids and Insulators. It decreases with increase of temperature. Substance. Specific Eesistance in ohms per cubic centimetre. Tempe- rature Bichromate of potash (saturated solution) 29-6 4-7 1-4 29-3 21-5 8-0 3-4  1015 Common salt, saturated 18 Nitric acid (density 1-36) '. Sulphate of copper, saturated 10 14 Sulphuric acid (density 1 "2) 12 Water 11 „ distilled Ebonite 46 Glass (below 40° C, very large) Guttapercha 46 24 Ice - 0-2 Mica 20 Paraffin 46 Shellac 28 PHYSICAL UNITS. 133 Table XVIII. Magnetic Elements in Different Parts of the British Isles for January 1, 1886, according to a recent survey by Profs. Riicker and Thorpe (Bakerian Lecture, Phil. Trans., 1890). — Declination. Dip. Horizon- tal force in dyne. Vertical force in dyne. Lerwick 20 30 21 43 20 47 21 12 20 26 19 9 18 45 18 5 18 34 17 55 18 16 19 29 21 41 22 18 o / 72 47 71 31 70 38 70 45 69 54 69 11 68 38 68 2 67 58 67 29 67 37 67 26 69 16 68 46 •1471 •1564 •1618 •1606 •1662 •1708 •1747 •1778 •1789 •1816 •1809 •1826 •1709 •1751 ■4748 Inverness •4660 Edinburgh •4606 ^Glasgow •4600 Carlisle ■4543 Leeds ■4492 Nottingham Cambridge ■4464 •4410 Oxford •4419 Oreenwich •4376 Kew •4395 Exeter •4395 Dublin •4513 Cork •4507 * The value of the horizontal component of the earth's mag- netism in the Physical Laboratory of the University of Glasgow determined by the Gaussian method, is '154 dyne. 134 PHYSICAL UNITS. Table XIX. Electro-chemical Equivalents, calculated on the basis of Lord Eayleigh's electro-cHemical equivalent of silver. Elements. Aluminium Copper (cupric)... „ (cuprous). Gold Hydrogen Iron (ferric) „ (ferrous) ... Lead Magnesium ...... Mercury (mer- curic) Mercury (mer- curous) Nickel Potassium Silver Sodium Tin (stannic) „ (stannous) ... Zinc Electro-negative : Bromine Chlorine Iodine Nitrogen Oxygen a -s, 27-3 63'0 63-0 196-2 1-0 55-9 55-9 206-4 23-94 199-8 199-8 58-6 39-04 107-66 22-99 117-8 117-8 64-9 79-75 35-37 126-53 14-01 15-96 o a o 9-1 31-5 63-0 65-4 10 18-64 27-95 103-2 11-97 99-9 199-8 29-3 39-04 107-66 22-99 29-45 58-9 32-45 79-75 35-37 126-53 4-67 7-98 -3 s a W IS 0-0925 0-3271 0-6542 0-6791 0-0104 0-1936 0-2904 1-0716 0-1243 1-0374 2-0747 0-3043 0-4054 1-1180 0-2387 0-3058 0-6116 0-3370 0-8281 0-3673 1-3139 0-0485 0-0829 o a o 10583 3058 1529 1473 96293 5166 3445 933 8045 964-0 482' 3286 2467' 894' 4188' 3270' 1635' 2967' a> s A o Si a S3 6< 0-3402 1-1770- 2 3540 2-4448 0-0374 0-6968 1-0448 3-8578 0-4475 3-7345 7-4690 1-0953 1-4595 4-0250 0-8594 1-1009 2-2018 1-2133 PHYSICAL UNITS. 135 Table XX. Linear Expansions of Solids. MeanExpan- Range, in Substance. Degree C. Degrees. Authority. into 10-ii. Aluminium, com- mercial 22-2 10-56 5-59 to 100 to 100 40 Calvert, Johnson, Low©' Matthiessen Arsenic, sublimed Fizeau 13-16 18-75 31-59 7-86 to 100 to 100 to 100 40 Matthiessen Brass, cast Smeaton Cadmium .'.... Matthiessen Carbon, graphite... Fizeau Cobalt 12-36 40 Fizeau Copper 18-66 to 100 Matthiessen Ebonite 7-70 16-7 to 25-3 Kohlrausch Glass, plate 8-91 to 100 Lavoisier and Laplac& Gold, annealed ... 14-70 to 100 Matthiessen Granite 8-68 to 100 Bartlett Ice 52-36 41-7 -27-5to-l-25 40 Schumacher Indium, cast Fizeau Iridium 7-0 11-90 27-99 40 to 100 to 100 Fizeau Calvert, Johnson, Lowe- Lead Matthiessen Magnesium, cast... 26-94 40 Fizeau Marble, white 10-72 to 100 Dunn and Sang Nickel 12-79 11-04 8-86 40 to 100 to 100 Fizeau Matthiessen Platinum Matthiessen Platinum - iridium (one-tenthiridium) 8-84 40 Fizeau Quartz fibre 8-7 46-5 to 71-3 Threlfall Sandstone 11-74 10 -.38 to 100 to 100 Adie Slate Adie Silver 19-43 to 100 Matthiessen Sodium 68-0 19-33 to 100 — Speculum metal ... Steel, soft Smeaton 10-3 Calvert, Johnson, Lowe Sulphur, Sicily ..^ 64-13 40 Fizeau Tin 22-96 to 100 Matthiessen Type metal (lead and antimony)... Zinc 20-33 29-76 16-6 to 100 to 100 Daniell Matthiessen 136 PHYSICAL UNITS. Table XXI. Volume and Density of Water and Mercury (water results reduced by Prof. W. H, Miller, from Kupffer's results, which gives the absolute density, 1-000013 at 4° C). Water. Mercury. Tempe- '^^' rature. ^^ C. P ce le Density Volume in Density in Volume of grammes cubic centi- grammes Mercury at 0° er cubic metres per per cubic C. taken as ntimetre. gramme. centimetre. unity. 999884 1-000116 13-596 1-000000 1 999941 1-000059 — — 2 999982 1-000018 — — 3 1 000004 -999996 — — 4 1 000013 -999987 13-586 1-000716 5 1 000003 -999997 13-584 1-000896 6 999983 1-000017 — — 7 999946 1-000054 — — 8 999899 1000101 — — 9 999837 1-000163 — — 10 999760 1-000240 13-572 1-001792 15 999173 1-000828 13-559 1-002691 20 998272 1-001731 13-547 1-003590 25 997133 1-002875 . — — 30 995778 1-004240 13-523 1-005393 35 99419 — — — 40 99236 1-007682 13-449 1-007201 45 99038 — 50 98821 1-011928 13-474 1-009013 60 98339 1-016906 13-450 1-010831 70 97795 1-022542 13-426 1-012655 80 97195 1-028856 13-401 1-014482 90 96557 1-035662 13-377 1-016315 100 95866 1-043117 13-353 1-018153 PHYSICAL UNITS. Table XXII. Specific Heats of Solids. 137 Solids. Aluminium Antimony Arsenic (crystalline) Bismuth Brass (4 Cu. 1 Sn ) Bromine » CJadmium ■Copper ■Glass •Gold 'Graphite Ice Iodine Iridium Iron Lead Magnesium Manganese Mercury Nickel Palladium Phosphorus (yellow) Platinum Platinum-iridium .. Potassium Silicon Silver Sodium .'. Sulphur Tin Zinc Specific Heat. ■2122 ■0486 ■0830 •0298 ■0858 ■0843 •0548 ■0933 ■198 •0316 •1604 •504 •0541 •0323 •1124 •0315 •245 •1217 •0319 •1092 •0592 1699 •0323 •0410 •1655 •1697 ■0559 •2934 •163 •0559 •0935 Temperature, Centigrade. 15 to 97 13 to 106 21 to 68 9 to 102 15 to 98 ■ 78 to - 20 to 100 15 to 100 to 11 20 to 9 to to 50 19 to 20 to 14 to ■78 to 14 to to 78 to to 100 98 100 48 51 97 -40 97 100 10 100 78 to 22 to 100 28 to 6 17 to 45 to 100 to 100 Authority. Eegnault Bfede Bettendorf &Wullner Bfede Eegnault Eegnault Bunsen Bfede VioUe H. F. Weber Eegnault Eegnault VioUe Bystrom Kopp Kopp Eegnault Eegnault Eegnault VioUe Eegnault Violle Eegnault H. F. Weber Bunsen Eegnault Kopp Bunsen Bunsen K Missing Page Missing Page 140 PHYSICAL UNITS. Table XXV. Thermal Conductivities, at Temperatures from 7° to 15° C. (a) Solids. Aluminium '344 Antimony '044 Bismuth -018 Brass -204 Cadmium -220 Copper -996 German silver '070 Iron -201 Lead -084 Magnesium at 100° C... -37 Phosphor bronze ■415 Silver 1-096 Tin -153 Zinc -28 Calico -000139 Cork -000397 Eiderdown -000108 Glass -0021 Fir, across fibre -00026 „ along „ -00047 Ice at 0° C -00568 Oak, across fibres -00059 Sandstone (Craigleith) -01068 Underground strata. . . -005 Walnut, across fibres -00029 „ along „ ... -00048 Wool -000122 Writing-paper, white -000119 (6) Liquids (from 9° to 15° C, by H. F. Weber). Alcohol, amyl -000328 „ ethyl -000423 „ methyl -000495 Aniline -000408 Benzol -000333 Bisulphide of carbon -000343 Chloroform -000288 Ether -000303 Glycerine 000670 Oil of turpentine ... -000260 Sulphuric acid -000765 Water -00136 (c) Gases (Winkelmann). Air -0000516 Carbonic acid -0000273 „ oxide -0000499 Hydrogen -00033 Marsh gas -000065 Nitrous oxide -0000312 PHYSICAL UNITS. 141 Table XXVI. Melting Points and Latent Heats of Fusion. Melting Points C°. Latent Heats of Fusion. Aluminium Antimony Bismuth Bromine Cadmium Cobalt Copper Gold Glass Ice Iodine Iridium Iron, cast (grey) — „ (white).... ,, wrought ,, steel, cast — Lead Manganese Mercury Nickel Palladium Phosphorus (yellow) Platinum Potassium Silver Sulphur, rhombic... Tin Zinc 850 432 268 -7 321 1500 1054 1045 1100 115 1950 1200 1100 2000 1375 326 1500 -39 1450 1500 44 1775 62 954 114 233 433 12-6 16-2 13-7 80-0 11-7 230 33-0 5-4 2-8 4-6 36-3 5-2 27-2 2M 9-4 14-3 28-1 142 PHYSICAL UNITS. Table XXVII. Boiling Points and Latent Heats of Evaporation. Substance. Air Alcohol, ethyl „ methyl •.... Ammonia Argon Benzol Bromine Carbon dioside — „ disulphide. „ monoxide Chlorine Chloroform Ether Glycerine Hydrogen Iodine Mercury Nitric oxide Nitrogen Olive oil Oxygen Ozone Phosphorus (yellow). Potassium Rose oil Sulphur Sulphuric acid Turpentine Water Zinc chloride C^H^O CH,0 H3N Ai Br CO, CSg CO CI CHC13 CsHgOg H I Hg NO N O3 P K S H2SO, H2O ZnCL Boiling Point C°. -191-4 78-4 66-3 - 33-7 -187 80-4 59-27 - 78-2 46-2 -190-0 - 33-6 61-2 34-97 290-0 - 243-5 250-0 357-25 -153-6 -194-4 315-0 - 182-0 -106-0 287-3 725-0 274-0 440 325-0 159-3 100-0  263-86 297-38 45-6 49-32 86-67 90-7 23-95 62-0 362-80 122-1 74-0 537-0 PHYSICAL UNITS. 143 Table XXVIII. Critical Temperatures and Pressures. to i^. g ■3 Ph a Eh © Ph ^ 2 Oi >, H d 0) ao &D n .•a Gas. Critical peratu Critical sure i mosph lb 2 .3 Freezin, sure ii of Hg. '1 Air -140-0 H- 234-6 39-0 65-0 — — Olszewski Alcohol . .. Hannay Argon -121 50-6 -189-6 — Olszewski Benzol 4-280-6 49-5 — — Sajotschewsky 'Carbonic acid + 30-92 73-0 — — Andrews Oarbon mon- oxide . .. -139-5 35-5 -207 100 Olszewski 'Carbon bi- sulphide -1-273-0 77-9 — — Hannay •Chloroform -(-260-0 54-9 — — Sajotschewsky Ether -1- 190-0 36-9 — — J) Hydrochlo- ric acid.. + 51-25 86-0 -116(0 Iszewski) Ansdell Hydrogen .. -234-5 20 — — Olszewski Nitric oxide -93-5 71-2 -167 138 )) Nitrogen . .. -146-0 35-0 -214 60 )) Nitrous oxide . .. -(-36-4 73-1 — — Janssen •Oxygen . .. -118-8 50-8 — — Olszewski Sulphurous acid -1-155-4 78-9 _ Sajotschewsky Water + 365 200-5 — — Cailletet 144 PHYSICAL UNITS. Table XXIX. Vapour Pressure of Water in Centimetres of Mercury. Tempera- ture C°. Pressure. Tempera- ture C°. Pressure. Tempera- ture C°, Pressure. -30 0-04 60 14-88 150 358-12 -25 0-06 65 18-69 155 408-86 -20 0-09 70 23-31 160 465-16 -15 0-14 75 28-85 165 527-45 -10 0-21 SO 35-46 170 596-17 - 5 0-31 85 43-30 175 671-75 046 90 52-54 180 754-64 5 0-65 95 63-38 185 845-32 10 0'92 100 76-00 190 944-27 15 1-27 105 90-64 195 1051-96 20 1-74 110 107-54 200 1168-90 25 2-35 115 126-94 205 1295-57 30 3-15 120 149-13 210 1432-48 35 4-18 125 174-39 215 1580-13 40 5-49 130 203-03 220 1739-04 45 7-14 135 235-37 225 1909-70 50 9-20 140 271-76 230 2092-64 55 11-75 145 312-55 — — Vapour Pressure of Mercury in Centimetres of Mercury (first four by Hertz ; rest by Kamsay and Young). •000019 60 -0029 140 -1763 10 -00005 70 •0052 160 -4013 20 -00013 80 •0092 180 -8535 30 -00029 90 -0160 200 1-7015 40 -0008 100 •0270 220 3-1957 50 •0015 120 •0719 — — PHYSICAL UNITS. Table XXX. 145. Emissivity — showing loss of heat, at atmospheric pressure, per square centimetre, per second, per 1° C. of excess of tempera- ture of cooling globe above temperature of surrounding enclosure {U°-5 C.) [Bottomley]. Phil. Trans., Vol. 184 (1893). Tempera- ture of Globe C°. Copp( Glob polish brigh 3r Copper G 3 thinly cov 3d with t. lampbia j^^^ Copper G ^^^"^ bright £ ck *^™^^ lacquer lobe " A Copper Globe ^"^"^ plated with \ silver. 3d. 21 165x1 0-e 278 X 1( )-6 246 X 1( )-6 _ 22 170 , 281 , 250 , , 23 174 , 284 , 254 , 174x10-6- 24 178 , 287 , 257 , 178 „ 25 181 , 290 , 260 , 182 „ 26 184 , 293 , 263 , 185 „ 27 187 , 296 , 265 , 187-5 „ 28 190 , 299 , 268 , 190 „ 29 192 , 301-5 , 271 , 192 „ 30 194 , 304-5 , 273 , 194 „ 31 196 , 307 , 276 , 196 „ 32 198 , 310 , 278 , 198 „ 33 199-5 , 313 , 280 , 200 „ 34 201 , 316 , 282-5 , 201 ,. 35 202 , 320 , 285 , 203 „ 36 203-5 , 323 , 287 , 205 „ 37 205 , 326 , 290 , 206-6 „ 38 206-5 , 329 , 292 , 208 „ 39 207 , 332 , 294 , 209-5 „ 40 208 , 335 , 297 , 211 „ 41 — 338 , 299 , 212-5 „ 42 341 , 301-5 , 214 „ 43 304 , 215 „ 44 307 , 216 „ 45 — 309 , 218 „ 146 PHYSICAL UNITS. Table XXXI. Indices of Refraction of Solids, Liquids, and Gases for the mean D line. {a) Solids. Alum 1-547 Borax 1-475 Canada balsam 1-532 Diamond 2-45 to 2-97 Emerald 1-585 Felspar 1-764 Fluorspar 1-436 <JlaBS (flint) 1-57 to 1-58 „ (crown) 1-525 to 1-534 ,, (plate) 1-514 to 1-542 Ice 1-310 Iceland spar (ord. ) 1 -658 „ (ext.) 1-486 Phosphorus 2-224 Quartz (ord.) 1-544 „ (ext.) 1-553 Rock salt — 1-545 Ruby 1-779 Sulphur (native) 2-115 Topaz 1-610 Tourmaline 1-668 (b) Liquids. Alcohol (rectified) 1 -372 Aniline 1-57 Benzene 1-49 •Carbon disulphide 1-678 Chloroform 1-44 Ether 1-358 •Glycerine 1-47 Hydrochloric acid (concen- trated) 1-410 Linseed oil 1-485 Nitric acid (sp. gr. 1-48) ... 1-410 Nut oil 1 Oil of almonds 1 ,, cassia 1 lavender 1 Olive oil 1 Phenol 1 Saliva 1 Sulphuric acid (sp. gr. 1 -7) 1 Turpentine 1 Water 1 -500 •469 ■031 •457 •470 •55 •339 •429 •46 •336 (c) Gases. — Den- sity. Index. — Den- sity. Index. Air rooo 0^596 1-957 1-524 2-470 1-806 2-580 0-069 1-000294 1-000385 1-000340 1-000449 1-000772 1-000834 1-000153 1-000138 ATarsh q'Sls 0-555 1-039 0-971 1-520 1-106 2-644 2-234 1-000443 Ammonia Nitric oxide Nitrogen _.. Nitrous oxide Oxygen Sulphide of carbon Sulphurous acid... 1 -onn.ws Carbon monoxide ,, dioxide... Chlorine 1-000300 1-000503 1 -000273 1 -000150 Ether Hydrogen 1-000665 PHYSICAL UNITS. 147 Table XXXII. 'Wave-lengths and Wave-frequencies, taking v = 3 x W-" cms. per Second (Watts). Designation and Origin. Wave-length in Air in 10-*5 cm. A B C(H) D (Na) I E(CaandFe) ii(Mg) *2(Mg) 63(NiandFe) *4 (Mgand Fe) E(H) .• 0(re) H(Ca) K(Ca) L(Fe) M(Fe) N(Fe) 0(Fe double) P(FeandTi) Q(Fe) K(FeandCa) r (Fe double) Si(]Sri double) 82 (Fe triple) ^(Fe) T(Fe double) ^(Fe) «(Fe) 7-6040 68670 6-5621 5-89513 5-88912 5-26913 5-18310 517216 5-16848 5-16688 4-86072 4-30725 3-9681 3-9330 3-8198 3-7270 3-5805 3-4398 3-3592 3-2849 31790 3-1443 3-1006 3-0995 3-0464 3-0197 2-9943 2-9478 Frequency per Second. 394-6 X 10^2 436-9 „ 457-2 „ 509-3 „ 569-4 „ 578-8 „ 579-9 „ 580-5 „ 617-2 „ 696-5 ,, 756-0 „ ^ 762-8 „ J 785-2 „ 805-0 „ 837-7 „ 872-0 „ 893-2 „ 913-1 „ 943-6 „ 954-1 „ 967-7 „ 985-4 „ 993-3 „ 1002 1017 „ Refractive Index of Air. 1-00029286 1-00029350 1-00029383 1-00029470 1-00029584 1-00029685 1-00029873 1-00030028 100030096 1-00030148 1-00030212 1-00030336 1-00030397 1-00030459 1-00030555 I IJTID EI 2?:. ^,^V^/%^^rw/N;V>/ A. Acceleration 25 Angular 25 Due to Gravity at Various Places 114 Activity 35 Air, Collected Data for Density of 98 Refractive Index for Diffe- rent Lights 147 Specific Heat of 139 Thermal Conductivity of ... 140 Ampere ... 74, 77, 82, 98, 103, 105 Ampere's Formula 81 Angle 24 Solid 24 Area, Unit of 24 Atmosphere 88, 98 Attraction, Constant of ... 17, 18 Newton's Law of 16, 17 B. B. A. Ohm 87 Ballistic Galvanometer 78 Board of Trade Ohm 87 Boiling Points, Table of 142 Candle, Standard 98 Candle-power 98 Capacities, Specific Inductive 124 Capacity, JElectrioal 58, 64 Measure of 89,90 Specific Inductive 66 Thermal 94 Capillary Tubes, Flow through 39> Carbon, Specific Resistance of 131 Centimetre 10, 11 in British Units 99" Centimetre-gramme in British Units 99' Tentimetre-dyne , 32, 99 Centrifugal I'orce 27 at Equator 28 OGS. System 10 Clark's Standard Cell .. 108, 109 Coefficient of Expansion ... 95 96 Coil, Rotating 84 Conductance 59 Conductivity of Copper at Different Temperatures,. 125^ Conductivity of Copper Wires 126 Thermal 96 Thermometrio 9T Constants, Table of Useful ... 98 Copper, Conductivity and Resistance of 125 Coulomb 74 Couple, Moment of 33 Critical Pressures 143 Temperatures 143 Current Balance 82 Current, Heat Generated by 83 Measurement of ,„ 80, 81, 82, 90 Standard of 105 Unit of 57,63 Curvature 24, 25- D. Day, Sidereal 15, 99' Solar 16, 19,20, 99- Declination, Magnetic, at Various Places 133 INDEX. Degrees of Longitude and Latitude 99 Densities o£ Solids 116 Liquids and Gases 117 Density 35 of Mercury 136 of Water 136 Derived Units 9 Diffusion 40 Diffusivity 40, 97 Dimensional Formulse 23 Uses of- 42 Dimensions of Electric and Magnetic Quantities 68 Dimensions oi k^ //.^ 69 Dyne 26, 99 E. Earth, Mass of 17 Size and Figure of 17, 26 Elasticity 36 Elasticity Waves, Table of Velocity of 119 Electric Force 57 Pressure, Standard of 105 Electric Quantities, Relations between 49 Electric Units, Measurement of 90 Electro-chemical Action 82 Equivalents, Table of 134 Electro-dynamics 81 Electro-dynamic Units ...... 49, 81 Electro-dynamometer 82 Electro-magnetic Units, 49, 55, 63 Dimensions of 59 Table of 59 Electrostatic Units 48 Dimensions of 59 Table of 59 Electromotive Force 50, 72 Due to Cutting Lines of Force 71 Measurement of 89, 90 Standard of 89 Emissivities, Table of 145 Emissivity 97 Energy 32 Electrical Unit of 99 Entropy 97 Equivalent, Mechanical, of Heat 101 Erg 32, 99 Examples in Theory of Units 42 to 47 F. Farad 74, 100 Field-Intensity 57, 60 Foot in Centimetres 100 Foot per Second 100 Foot-pound and Foot-poundal 32, 100 Foot-pound in Ergs 43, 100 Force, Unit of 25 32,33 Dimensional Formula for 28 Electric 57 between Electric Current and Magnetic Pole 54 of Gravity 26,27 between Two Quantities of Electricity 52, .56 Fundamental Units 9, 10 Symbols for 22 G. g. Value of, at Various Places 114 Gallon 100 Galvanometer, Ballistic 78 Gases, Densities of 117 Molecular Data for 123 Specific Heats of 139 Specific Inductive Capacities of 124 Gauss as Unit 92 Gilbert as Unit 92 Grain H Grain per inch 100 Gramme- weight 13, 26, 100 PerSq. Cm 100 Gravity, Terrestrial, 26, 27, 28, 29 Acceleration Due to, at Different Places 114 Gyration, Radius of 33 INDEX. H. Heat 93 Dynamical Equivalent of . . . 93 Generated by Current 88 Unit of 93 Henry 100 Homogeneous Atmosphere ... 123 Horse-power 85, 100 Horse-power Hour 100 I. Ice, Density of 116 Specific Heat of 137 Inch 101 Indices of Refraction 146 Induction, Magnetic 61, 62 Inertia, Moment of 33 Moments of (Table) 115 Insulators, Resistance of 132 Intensity of Electric Field ... 57 Magnetic Field 60 Magnetisation 61 J, Joule as Unit 32, 75, 101 Joule's Equivalent 101 K, Kepler's Laws 19 Newton's Deductions from 19, 20 Kilogramme 11, 12 101 PerSq. Cm 101 Kilowatt 76, 101 Kilowatt-hour 76, 99 Kinematics 28 Kinetic Energy 32 Knot 25, 101 Admiralty 101 L. Latent Heat 95 of Steam .... 95 Latent Heats of Evaporation 142 Fusion . 141 Latitude Degree of 99^ Length, British Unit of .... 10 French Unit of 10 Length Modulus 47 Length Moduluees 48 Light, Velocity of 147 Wave-Lengths 147 Linear Expansions of Solids. 135 Litre 101 Longitude, Degree of 99 M. Magnetic Elements in Diffe- rent Parts of British Isles 133- Magnetic Induction ,61,62 Permeability 60 Pole 60 Susceptibility 61 Units, Table of 61 B. A. Discussion on 92: Dimensions of 61 Mass and Weight 12, 13 Mass, British Unit of 11 French Unit of 11 Standards of 11 Mechanical Equivalent of Heat 101 Megohm 101 Melting Points, Table of 141 Mercury, Inch of 101 Density and Volume of, at Different Temperatures.. 136 Vapour, Pressures of 144 Metre 10, 101 Microfarad 76 Microhm 101 Micromillimetre 101 Mile per Hour 101 Modulus of Elasticity 35 Bulk 36 Rigidity 36 Young's 36 Moduluses. Table of 118 Molecular Data for Gases 123- Molecules of Gases, Diameter of 123- INDEX. IV Molecules, Mean Path of 123 Number of Collisions per Second 123 Velocity of 123 Moment of Magnet 6C Inertia 33 Moments of Inertia 115 Momentum 25 Moment of 33 Mutual Induction 65 N. Newtonian Velocity of Sound in Various Gases 123 Nodes 20 Numeric 23 Oersted as Unit 92 Ohm 74, 87, 101, 108, 104 Ohm's Law 50 Pappus' Theorems 113 Pendulum, Seconds at Diffe- rent Places 114 Potential, Electric .„ 58 Magnetic 60 Pound, in Grains and in Grammes 101 per Square Inch 102 Standard 11, 14 Troy 11 Poundal 26, 102 Pound-weight in Poundals, 13, 26 Practical Units 70 in Terms of Absolute C.G.S. Units 76, 77 Pressure, Electrical, Standard of 105 Problems on Units 42 to 47 Q- Quadrant ...„ 100 Quantity of Electricity, Unit I of... 50, 5S Electromagnetic Unit 64 Electrostatic Unit 56 Measurement of 77, 90 Work done in Raising Poten- tial of 64 R. Eadian 24, 102; Radius of Gyration 33- Ratios of Electric Units 70 Specific Heats of Gases 139' Refraction Indices 146 Resistance 59, 65' Resistance Expressed by a Velocity 73 of Copper at Different Tem- peratures 125 of Copper Wires 126 Measurement of, 83, 84, 85, 86, 90 Relation between Units of 87 Standard of 104 Rigidity, Flexural 37 Torsional 37 Rotating Coil 84 Disc 85 Rotational Motion, Analogues of, to Translational 34 Secohm lOO' Second, Mean Solar 15, 20 Sidereal 15 Solar 1ft Second's Pendulum, Length at Different Places 114 Self-induction 65 Shear 36 Siemens' s Unit 87 Sound, Velocity of 123- Specific Gravities 116 Gravity 35 Heat 94 INDEX. Specific Heat of Water 95 Heats of Solids (Table) 137 Liquids 138 Gases • 139 Ratio of 139 Inductive Capacity 56 Capacities (Table) 124 Resistance of Alloys at Different Temperatures 130 of Carbon at Different Temperatures 131 of Liquids and Insulators at Different Tempera- tures 132 of Pure Metals at Diffe- rent Temperatures 129 Standard of Electric Curi-ent 105 Pressure 105 Resistance 104 Strain 36 Stress 36 Surface Density, Electric ... 57 Magnetic 60 Surfaces of Solids 113 Surface Tension 38 Tensions, Table of 120 T. Thermal Capacity 94 Conductivity 96 Conductivities, Table of ... 140 Time, Unit of 15 Variable 15 Units Suggested 21 Ton 102 Per Square Inch 102 Tortuosity 24 u. Units, Geometrical and Kine- matical 23 Relation between British and Metric 12 Table of 41 Table of Dimensions of, 41, 59, 62, 66, 68, 70 V, Determinations of 91 Vapour Pressures of Mercury 144 Water 144 Velocity 25 Angular 25 of Light 70, 147 of Sound, Newtonian 123 of a Wave-motion 47 Viscosity 88, 89 of Gases, Table of 122 of Liquids, Table of 121 Volt 72, 104, 105 Voltameter, Silver 106, 107 Volume of Mercury 136 of Water 136 Elasticity of 86 Unit of 24 W. Water, Density of 102, 186 Expansion of 136 Vapour Pressures of 144 Volume at Different Tem- peratures 136 Watt as Unit „ 35, 75, 102 Wave-frequencies 147 Wave-lengths 147 Weber as Unit 92 Weight and Mass ,12, 13, 14 Weight not Invariable 13 Weight of Copper Wires 126 Wires, Board of Trade Gauge 126 Work 31, 32, 33 Done by Current 51, 52 in Raising Electric Potential 74 Working, Rate of 35 Y. Yard , 10, 102 Tard Measure, Standard ... 10, 14 Year, Civil 102 Sidereal 102 Young's Modulus 36 BIGGS & CO.'S BOOK-LIST. ELECTRICAL ENGINEERS' SERIES. Tirst Principles of Electrical Engineering. Second Edition. Crown 8vo. Price 2s. 6d. By C. H. W. Biggs, Editor of The Electrical Engiiieer and The Gontracf, Jouriial. First Principles of Mechanical Engineering. By John Ijiray, with additions by C. H. "W. Biggs. Illustrated. Price 3s. 6d. Pirst Principles of Building : Being a Practical Handbook for Technical Students. By Alex. Black, C.E. Illustrated. Price 3s. 6d. Pirst Principles of the Locomotive By Michael Reynolds. Illustrated. Price 2s. 6d. Portative Electricity By J. T. Niblett, author of " Secondary Batteries. " Illustrated. Price 2s. 6d. Popular Electric Lighting. By Captain E. Ironside Bax. Illustrated. Price 2s. Practical Electrical Engineering. Being a complete treatise on the Construction and Management of Electrical Apparatus as used in Electric Lighting and the Electric Trans- mission of Power. 2 Vols. Imp. Quarto. By Various Authors. With many Hundreds of Illustrations. Price £2. 2s. Dynamos, Alternators, and Transformers. By GisBBET Kapp, M.InstC.E., M.Inst.E.E. Fully Illustrated. Price 10s. 6d. The book gives an exposition of the general principles underlying the construction of Dynamo - Electric Apparatus without the use of high mathematics and complicated methods of investigation, thus enabling the average engineering student and the average electrical engineer, even without previous knowledge, to easily follow the subject. Xllectric Tractioa. By A. Reokenzaun, M.I.E.E. Illustrated. Price 10s. 6d. This is the first serious attempt to consolidate and systematise the information of an important subject. Mr. Reckenzauu's experience is of the longest and widest, and this book deals not only with the scientific and practical problems met with in traction work, but enters some- ivhat into the financial aspect of the q^uestion. Electrical Distribution : Its Theory and Practice. Part I. : By Maetin Hamilton Kilgoub. Part II. : By H> Swan and C. H. W. Biggs. Illustrated. Price 10s. 6d. Electric Ligrbt and Po-wer : Giving the Results of ■ Practical Experience in Central-Station Work. By Arthur F.. Guy, A.M.I.C.E. Illustrated. Price 5s. Alternate - Current Transformer Design By E. W'. Weekes, WhitSch., A.M.I.C.E. Crown 8vo. Illus- trated. Price 2s. This book is one of a new series intended to- show engineers and manufacturers the exact method of using our acquired knowledge in the design and construction of apparatus.. Town Councillors' Handbook to Electric Lie:htin^. By N. SooTT Russell, M.Inst.C.E. Crown 8vo. Illustrated.. Cloth, Is. Physical Units. By Magnus Maclean, M.A., D Sc, F.R.S.E. Illustrated. Price 2s. 6d. This little book discusses the present state of the subject under the following headings :. Fundamental Units — Geometrical and Kinematical Units — Dyna- mical Units — Electrostatic System of Units — Magnetic Units — ' Electi-omagnetic System of Units — Practical Electrical Units. Secondary Batteries. By J. T. Niblett. Illustrated. The Second Edition of this .Work will shortly be issued, the^ price of which will be 5s. Theory and Practice of Electro - Deposition i Including every known mode of Depositing Metals, Preparing- Metals for Immersion, Taking Moulds, and Rendering them Conducting. By Dr. G. Gore, F.R.S. Crown 8vo. Illustrated.. Price Is. 6d. Alternating and Interrupted Electric Currents. By Prof. George Forbes, M.A., F.R.S., M.I.C.E. Illustrated. Price 2s. 6d. Economics of Iron and Steel. By H. J. Skelton. Illustrated. Price 5s. IN THE PRESS. First Principles of Electricity and Magnetism. By C. H. W. Biggs, M.I.E.E., Editor of The Mectrical Engineer.. Illustrated. Price 2s. 6d. This book has been prepared' more especially to assist students for the elementary examinations for the City and Guilds Institute. Central - Station Management. By J. Hesketh, M.I.E.E., etc.. Borough Electrical Engineer, Blackpool. MUNICIPAL ENGINEERS' SERIES. Tlefuse Deitructors, with Results up to Present Time Second and Revised Edition. A Handbook for Municipal Officers, Town Councillors, and others interested in Town Sanitation. By Charles Jones, M.Inst.C.E., Hon. Sec. and Past-President of the Incorporated Association of Municipal and County Engineers ; Surveyor to the Ealing Local Board. With a Paper on "The Utilisation of Town Refuse for Power Production," by Thomas TiiiMLixsox, B.E., A.M.I. C.E. With numerous Diagrams. Price 5s. The Contractors' Price-Book. By E. De Verb Buck- ingham. Crown 8vo. 800 pages. Price 5s. It would be some- what difficult to prove that a want exists in any direction ; but, as a matter of fact, while there are price-books in all directions and, seemingly, of every kind, it has been found from practical ex- perience that not one of these books is of much assistance to large contractors — by large contractors, we refer to such as are engaged in railway, dock, sewage, canal, water, and other works. This book is compiled to supply their needs, and will be published, corrected to date, annually. The Construction of Carriageways and Footways By H. P. BoFLXOis, M.I.C.E., Past-President of Municipal and County Engineers, City Engineer of Liverpool. Demy Bvo. Illustrated. Price 5s. Sewerage and Sewage Disposal of a Small Town. By E. B. Savage, A. M.I. C.E. DemySvo. Illustrated. Price 5s Illanaerement of Highways. By E. Puenell Hoolby, A.M. I. C.E. , County Surveyor of Nottinghamshire. Demy Bvo. Price Is. IN THE PRESS. Water Supply in Rural Districts. By R. Godfrey, A. M.Inst.C.E., Surveyor to the Rural Sanitary Authority, King's Lynn. Demy 8vo. Illustrated. Price 5s. House Drainage. By W. Spines, A.M.Inst.C.E., Lecturer on Sanitary Engineering, Yorkshire College, Victoria University. Designs and Discharging Capacities of Sewers, With Rules and Tables. By Santo Crimp, M.Inst.C.E., author of "Sewage Disposal." Highway Bridges. By E. P. Silcock, A M.Inst.C.E., Borough Surveyor, King's Lynn. Street and Town Sanitation. By C. Mason, M.Inst. C.E., Surveyor, St. Martin's-in-the-Fields, London, W.C. rrxK£: ELECTRICAL ENGINEER A JOURNAL OF ELECTRICAL ENGINEERING, WITH WHICH IS INCORPORATED "ELECTRIC LIGHT." (EDITED BY C. H. W. BIGGS. This Paper is absolutely independent of and uncontrolled by men interested in particular companies. These men run papers to suit their own purposes — to get early information for themselves, not to give information to the Profession. Published every Friday. Price 3d. Subscription, Post Free, within the United Kingdom 13s. per annum ; other places 17s. 4d. per annum. For Aduertisement Charges apply to the Adver- tisement Manager, 139-40, SALISBURY COURT, LONDON, E.G. PRACTICAL ELECTRICAL ENGINEERING: Being a complete treatise on the Construction and Management of Electrical Apparatus as used in Electric Lighting and the Electric Transmission of Power. 2 Yols. Imp. Quarto. By various AUTHORS. With many Hundreds of Illustrations. PRICE £2 2s. Od. Among the information collected in and written specially for these volumes, are complete monographs by Mr. Gisbebt Kapp, M.Inst.C.E., on Dynamos, giving the principles on which the construction of these machines is founded, and a vast amount of new information as to the constructive details. Mr. Anthony RscKENZAnN, M.Inst.E.E., considers the whole question of Electric Traction on Railways and Tramways, describing the most recent practice and giving exhaustive details not only of the mechanism, but of practical considera- tions which are of the utmost commercial importance. Mk. C. Capiio, M.Inst.E.E., deals with Steam — and considers the theory — as well as the practical construction of boilers and engines, more especially in connection with electric lighting and transmission of power. This section alone con- tains no less than 371 illustrations. Mr. Hamilton EaLoouR considers carefully the theory of Elec- trical Distribution, upon which depends the right proportioning of mains in order to secure economical distribution. Other men have collected a complete description of the various systems practically applied, the materials used and methods of construction. The above form but a portion of these volumes, which should prove of the utmost value to everyone who professes to be an Electrical Engineer. BIGGS & CO., 139-140, SALISBURY COURT, LONDON, E.G. DYNAMOS, ALTERNATORS, AND TRANSFORMERS. By GiSBEET Kapp, M.Inst.C.E., M.Inst.E.E. Fully Illustrated. Price 10s. 6d. The book gives an exposition of the general principles under- lying the construction of Dynamo-Electric Apparatus without the use of high mathematics and complicated methods of investigation, thus enabling the average engineering student and the average electrical engineer, even without previous knowledge, to easily follow the subject. CHAPTER I. — Definition. EfSciency of Dynamo-Electric Apparatus, etc. CHAPTER II.— Scope of Theory. The Magnetic Field, etc. CHAPTER III.— Magnetic Moment. Measuring Weak Magnetic Fields. Attractive Force of Magnets. Practical Examples, CHAPTER IV.— Action of Current upon Magnet. Field of a Current. Unit Current, etc. CHAPTER v.— The Electromagnet. The Solenoid. Magnetic Permeability. Magnetic Force, etc. CHAPTER VI. — Magnetic Properties of Iron. Hysteresis. CHAPTER VII. -Induced Electromotive Force, etc. CHAPTER VIII.— Electromotive Force of Armature, etc. CHAPTER IX.— Open-Coil Armatures. The Brush Armature, etc. CHAPTER X.— Field Magnets. Two-Pole Fields, etc. CHAPTER XI. — Static and Dynamic Electromotive Force, etc. CHAPTER XII. — Influence of Linear Dimensions on the Output. Very Small Dynamos. Critical Conditions, etc. CHAPTER XIII.— Loss of Power in Dynamos, etc. CHAPTER XIV.— Examples of Dynamos. CHAPTER XV. — Elementary Alternator. Measurement of Electromotive Force, etc. CHAPTER XVI.— Working Conditions. Effect of Self-induction, etc. CHAPTER XVII.— Elementary Transformer. Effect of Leakage, etc. CHAPTER XVIII.— Examples of Alternators. We can heartily recommend it. — Electrical Engineer. A valuable contribution to electrical literature. — Electrical World. Invaluable to the advanced student and dynamo designer. — Electrician. The reader will find valuable information concerning dynamo design. — Nature. BIGGS & CO., 138-140, SALISBURY COURT, LONDON, EC. ELECTRIC TRACTION. By A. Reokbnzaun, M.I.E.E. Illustrated. Price 10s. 6d. This is the first serious attempt to consolidate and systematise the information of an important subject. Mr. Eeokenzaun's experience is of the longest and widest, and this book deals not only with the scientific and practical problems met with in traction work, but enters somewhat into the financial aspect of the question. CHAPTER I.— Early History. Magnetic Fields. Torciue. Motor Efficiency. Insulation Resistance. Brake Tests. Electri- cal Horse-Power. CHAPTER II.— Traction. High Pressure. Current, Stopping and Starting. Current Running. Energy Used. CHAPTER III.— Advantages of Two Motors on Each Oar. Calculations for Armatures. Constructive Details for Motors. Types of Tramcar Motors. Method of Suspen- sion. Brushes and Brush-holders. Switches and Speed- Regulating Devices. Motor Trucks. Important Points in Tramcar Motors. Gearless Motors. Mechanical Transmission between Motor and Axle. CHAPTER IV. — Description of Principal Systems of Overhead and Underground Construction used in Electric Traction. Poles. Trolleys and Trolley Wire. Overhead Curve Construction. Practical Hints on Overhead Construction. Insulators used in Electric Railway Work. Switchboards. Lightning Arresters and Cut-Outa. CHAPTER V. — Secondary Batteries. Weight and Efficiency Deterioration. CHAPTER VI. Portrush, Bessbrook-Newry, City and South London Railways. Central London Railway, Blackpool, Budapest, Leeds, and Halle Electric Tramways, West End Railway, Boston. CHAPTER YIl.—B^vmd of Writings and Expressions of Promi- nent Electrical Engineers on Electric Traction. HAPTER VIII.— Details of Working Expenses. Will be of great use as a reference to all tramway engineers, and will be invaluable to electrical engineers commencing traction work. — Electrical Engineer. His book is certainly interesting and instructive.— .BiscJricaJ Review. The most useful to English rea-deia.— Engineer. ■\.'\.'VVVV\."V' BIGGS & CO., 139-140, SALISBURY COURT, LONDON, E.G. ELECTRIC LIGHT AND POWER : Giving the Results of Practical Experience in Central- Station Work. By Arthur F. Guy, A.M.I.C.E. Illustrated. Price 5s. CHAPTEB I.— Evolution of Electrical Engineering : The First Electric Light — Subsequent Progress — Electricity in England and Abroad— Economics of the Electric Light — Sources of Power — Conservation of Energy, etc. CHAPTER II,— Motive Power : Coal as. Fuel— Plotting Curves- Steam Boilers, Engines, etc. — Running Cost of Steam and Gas Engines — Dowson and other Gas Producers — Petroleum Oil-Engine — Water Power, etc. CHAPTER III.— Practical Laws of Electricity and Magnetism : Sources of Electricity — Electrical Units — Calculation of Resistance — Conductors and Insulators— Simple and Divided Circuits — Magnets and Magnetism — The Magnetic Circuit, etc. CHAPTER IV.— Electric Machinery : Generation of Current- Field Magnet and Armature Winding — Working in Parallel — Notes on Running — Cost and Output of Dynamos — Electromotors, etc. CHAPTER V. — Electric Arc and Incandescent Lighting : Illuminating Power of Arcs — Consumption of Carbon — Diffusion of Light — Fixing and Trimming— Arcs in Parallel — Town-Lighting — Life and Efficiency of Lamps, etc. CHAPTER yi.— Distribution of Electric Power: Low-Pressure System — Loss in Mains — High-Pressure System — Use of Three and Five Wires — Alternate-Current Working — Transformers — Insulation — Testing Circuits — Traction Notes — Cost of Electric Energy, etc. Some books, like the pedlar's razors, are made to sell rather than for use : Mr. Guy's volume is not one of these. It has been issued for the purpose of placing on record useful practical knowledge obtained by the author during several years' expe- rience of central-station work, together with brief explanations of the laws which govern the action of electrical apparatus in general use for electric lighting. This brief description shows clearly the ground covered. There are many similar books in the market, but we do not know of one better suited to give the manipulator of electric dynamos an intelligent knowledge of the forces with which he has to deal, — Nature. BIGGS & CO., 139-140, SALISBURY COUKT, LONDON, S.C. 