Diagram of variation under different rules.
The incidence of this rule is clearly enough shown by the diagram, where the possible dimensions for a 10-, 20-, 30-, and 40-tonner are plotted under both rules; the two curves crossing at a point where the vessel is about 5-¼ beams in length. Below this point the new rule was easier on beam, and above it more severe; and it was thought that the extra beam admissible below the five-beam point would have induced builders to avail themselves of this quality; but beam, as we learn by the light of later years, was then altogether undervalued, and length was taken at any price, with the result that the adoption of extreme proportions was hastened rather than averted, till in 1886 a radical change in the rule was demanded, and in the autumn of that year a Committee of the Yacht Racing Association, after taking most exhaustive evidence from the various experts, decided on the adoption of a rule proposed by Mr. Dixon Kemp, based solely on length (which was measured on the load-water-line) and on sail-area.
In this rule, breadth, so sorely taxed by the 94 rule, was left absolutely unfettered; depth as heretofore being also untaxed, so that infinite scope was left for experiment in the way of beam. Simultaneously with this change, the use of the centreboard was permitted; and, as the pessimists declared, the road made clear for all manner of skimming dishes and consequent caprices. I ventured to point out at the time the possible dangers of unlimited beam, and proposed that the rule should be (L +B) × sail-area/constant; but this limitation was held to be unnecessary, as, indeed, it appeared to be for a year or two. With the exception of the 'Thistle,' built immediately on the passing of the rule, and built probably more with a view to American racing than performance in home waters, builders were somewhat chary of availing themselves of the advantages of beam, and, in the larger classes at least, successive yachts, though getting broader, only 'slowly broadened down from precedent to precedent.' To Mr. Alfred Payne, of Southampton, is due the credit of showing what could be done with large beam and moderate displacement.
In 1889 he built the 'Humming Bird,' 2½-rater, for Captain Hughes; this boat was 26 feet on water-line, 7.5 feet beam—that is, 3.46 beams in length—and was extremely successful against other and narrower boats, notably 'Thief' and 'Queen Mab', of like rating and designed by the writer.
Elements of 40-Raters (Length and Sail Area Rule)
| Description | Mohawk | Deerhound | Creole | Thalia | Varuna | Centreboard cutter — Queen Mab | Lais | Vendetta |
| Length on load line | 61.23 ft. | 58.85 ft. | 59 ft. 6 in. | 59.14 ft. | 59 ft. | 59 ft. 8 in. | 59.92 ft. | 59.96 ft. |
| Breadth extreme | 14.5 ft. | 13 ft. 5 in. | 13 ft. 2¼ in. | 13.9 ft. | 14 ft. 7 in. | 16 ft. 4 in. | 17 ft. | 17.05 ft. |
| Draught of water extreme | 9.5 ft. | 11 ft. 6½ in. | 12 ft. | 12 ft. 6 in. | 13 ft. 4 in. | 10 ft. 9 in. | — | — |
| Displacement | 58.8 tons | 58 tons | 58 tons | 57 tons | 55 tons | 54.8 tons | — | — |
| Designer | C. P. Clayton | G. L. Watson | G. L. Watson | W. Fife jun. | G. L. Watson | G. L. Watson | W. Fife jun. | A. E. Payne |
| Date when built | 1888 | 1889 | 1890 | 1891 | 1892 | 1892 | 1893 | 1893 |
In 1890 'Iverna' was built, of practically the same length as, and of less beam than, 'Thistle,' and no great advance was made until the present year (1893) in the adoption of beam in the larger classes; but the progress in this direction may be easily traced in the 'forty' and 'twenty' rating classes, where the growth of beam and decline in displacement are very well marked, as the table and diagram show.