In all physical magnitudes that are made use of, we have: (1) the physical magnitude itself, aside from the units that serve to measure it; (2) the C.G.S. unit that serves to measure such grandeur (granted the adoption of the C.G.S. system); (3) practical units, which, in general, have a special name for each kind of magnitude, and are a decimal multiple or sub-multiple of the C.G.S. unit, except for time and angles; (4) finally, decimal multiples and sub-multiples of these practical units, that are in current use.
The committee likewise decided always to adopt a large capital to designate the physical magnitude; a small capital to designate the C.G.S. unit, when it has a special name; a "lower case" letter for the abbreviation of each practical unit; and prefixes, always the same, for the decimal multiples and sub-multiples of the practical units.
Thus, for example, work would be indicated by the letter W (initial of the word); the C.G.S. unit is the erg, which would be written without abbreviation, on account of its being short; and the practical units would be the kilogrammeter (kgm), the grammeter (gm), etc. The multiples would be the meg-erg, the tonne-meter (t-m), etc.
Mr. Jamieson's propositions have been in great part approved. Some criticisms, however, were made during the course of the discussion, and it is for this reason that the scheme still remains open to improvements. The proposed symbols are as follows:
| A.—PRACTICAL ELECTRICUNITS. | |
| Total resistance of a circuit. | R |
| Internal resistance of a source of current. | r1 |
| Resistance of the separate parts of acurrent. | r1, r2,etc. |
| Specific resistance. | ρ |
| 1 ohm. | ω |
| 1 megohm. | Ω |
| Intensity of a current. | C |
| Magnitude of 1 ampere. | A |
| 1 milliampere. | α |
| Electro-motive force. | E |
| Magnitude of 1 volt. | v |
| Capacity. | K |
| Constant of specific induction. | σ |
| 1 farad. | Φ |
| 1 microfarad. | φ |
| Quantity of electricity. | Q |
| 1 coulomb. | C |
| Electric work (volt coulomb). | vC |
| Electric effect (volt ampere, watt in onesecond). | W |
| Horse power. | HP |
| B.—MAGNETISM. | |
| Pole of magnet pointing toward the north. | N |
| The opposite pole. | S |
| Force of a pole, quantity of magnetism. | m |
| Distance of the poles of a magnet. | l |
| Magnetic moment. | M = m.l |
| Intensity of magnetization. | J |
| Intensity of the horizontal component ofterrestrial magnetism. | H |
| C.—ELECTRIC MEASUREMENTS. | |
| Galvanometer and its resistance. | G |
| Resistance of the shunt of a galvanometer. | s |
| Battery and its internal resistance. | B |