| Interval pin parts of an inch | ||||
| Constant interval nbetween B and D = 1 inch | When the small ball B wasinductric and positive the discharge was all | When the small ball B was inductric and negativethe discharge was all | ||
| at p in air before | atn in the gas after | at p in airbefore | at n in thegas after | |
| In Air | 0.10 | 0.50 | 0.28 | 0.33 |
| In Nitrogen | 0.30 | 0.65 | 0.31 | 0.40 |
| In Oxygen | 0.33 | 0.52 | 0.27 | 0.30 |
| In Hydrogen | 0.20 | 0.10 | 0.22 | 0.24 |
| In Coal Gas | 0.20 | 0.90 | 0.20 | 0.27 |
| In Carbonic Acid | 0.61 | 1.30 | 0.30 | 0.15 |
1508. These results are the same generally, as far as they go, as those of the like nature in the last series (1388.), and confirm the conclusion that different gases restrain discharge in very different proportions. They are probably not so good as the former ones, for the glass jar not being varnished, acted irregularly, sometimes taking a certain degree of charge as a non-conductor, and at other times acting as a conductor in the conveyance and derangement of that charge. Another cause of difference in the ratios is, no doubt, the relative sizes of the discharge balls in air; in the former case they were of very different size, here they were alike.
1509. In future experiments intended to have the character of accuracy, the influence of these circumstances ought to be ascertained, and, above all things, the gases themselves ought to be contained in vessels of metal, and not of glass.
* * * * *
1510. The next set of results are those obtained when the intervals n and o (fig. 131.) were made equal to each other, and relate to the greater facility of discharge at the small ball, when rendered positive or negative (1493.).
1511. In air, with the intervals = 0.4 of an inch, A and B being inductric and positive, discharge was nearly equal at n and o; when A and B were inductric and negative, the discharge was mostly at n by negative brush. When the intervals were = 0.8 of an inch, with A and B inductric positively, all discharge was at n by positive brush; with A and B inductric negatively, all the discharge was at n by a negative brush. It is doubtful, therefore, from these results, whether the negative ball has any greater facility than the positive.
1512. Nitrogen.—Intervals n and o = 0.4 of an inch: A, B inductric positive, discharge at both intervals, most at n, by positive sparks; A, B inductric negative, discharge equal at n and o. The intervals made = 0.8 of an inch: A, B inductric positive, discharge all at n by positive brush; A, B inductric negative, discharge most at o by positive brush. In this gas, therefore, though the difference is not decisive, it would seem that the positive small ball caused the most ready discharge.
1513. Oxygen.—Intervals n and o = 0.4 of an inch: A, B inductric positive, discharge nearly equal; inductric negative, discharge mostly at n by negative brush. Made the intervals = 0.8 of an inch: A, B inductric positive, discharge both at n and o; inductric negative, discharge all at o by negative brush. So here the negative small ball seems to give the most ready discharge.
1514. Hydrogen.—Intervals n and o = 0.4 of an inch: A, B inductric positive, discharge nearly equal: inductric negative, discharge mostly at o. Intervals = 0.8 of an inch: A and B inductric positive, discharge mostly at n, as positive brush; inductric negative, discharge mostly at o, as positive brush. Here the positive discharge seems most facile.
1515. Coal gas.—n and o = 0.4 of an inch: A, B inductric positive, discharge nearly all at o by negative spark: A, B inductric negative, discharge nearly all at n by negative spark. Intervals = 0.8 of an inch, and A, B inductric positive, discharge mostly at o by negative brush: A, B inductric negative, discharge all at n by negative brush. Here the negative discharge most facile.