Roberts: The Founders of the Art of Breeding 235 



rare instances have still occurred in 

 these tedious and wearisome investiga- 

 tions, where the suspicion had made 

 itself felt, of a mistake or error having 

 crept in, either in pollination or emas- 

 culation, since such results stood in di- 

 rect contradiction to the usual ex- 

 periences, and on a repetition of the 

 experiments, made itself incontroverti- 

 bly evident as an error. We believed it 

 possible to attain no higher degree of 

 certainty in this branch of natural sci- 

 ence, and to be able to bring the con- 

 clusions derived therefrom to no higher 

 proof, than through the precise coinci- 

 dence of the forms of the products, by 

 repetition under the same conditions 

 with the same species, but with differ- 

 ent individuals, and at different times" 

 (p. 675). 



THE ENGLISH BOTANISTS * 



At the beginning of the nineteenth 

 century, there began to appear, in 

 England, the first signs of the applica- 

 tion of the science of hybridization to 

 the practical art of breeding, in the work 

 of Thomas Andrew Knight and William 

 Herbert. 



THE WORK OF KNIGHT 



Knight was a country gentleman by 

 occupation, born August 12, 1759, and 

 educated at Oxford, and who early 

 began to interest himself, on his estate 

 at Elton in Herefordshire, in experi- 

 ments in the raising of new varieties of 

 fruits and vegetables. In 1795 his 

 work as a horticulturist first became 

 known through some papers read at 

 the sessions of the Royal Society. He 

 was an organizer of the Horticultural 

 Society of London, founded 1804, of 

 which he was president from 1811 until 

 his death in 1838. He was an annual 

 contributor to its "Transactions" and 

 was the author of upwards of one hun- 

 dred papers. In 1841, three years after 

 his death, a collection of eighty-two of 

 his papers was published by the botan- 

 ists Bentham and Lindley. Of Knight's 

 published papers, forty-six are enumer- 

 ated in the Royal Society's Catalogue. 

 Knight was not a scientific man, but a 

 practical horticulturist with scientific 



instincts, who proceeded on the princi- 

 ple that the improvement of plants 

 depended upon the same scientific 

 laws as the improvement of animals, 

 and that cross-breeding was the key to 

 the origination of new and improved 

 sorts. His principal work of crossing 

 was carried out with currants, grapes, 

 apples pears, and peaches, to the end 

 of producing hardier and superior fruits. 

 One of his discoveries of genetic interest 

 was that, in crosses of varieties of red 

 upon white currant, by far the greater 

 number of the hybrids produced red 

 fruit, i.e., the dominance of red. A 

 conclusion formulated by Knight on 

 the basis of his experience, and after- 

 wards confirmed by Darwin, and since 

 called the Knight-Darwin law, was that 

 "new varieties of every species of fruit 

 will generally be better obtained by in- 

 troducing the farina (pollen) of one 

 variety of fruit into the blossom of an- 

 other, than by propagating from one 

 single kind." 



However, the work of Knight that 

 attracts the most attention from the 

 standpoint of genetics is his experiment 

 with peas. The paper in question, 

 read before the Horticultural Society, 

 June 3, 1823, was entitled: "Some 

 Remarks on the Supposed Influence of 

 the Pollen, in Cross-breeding, on the 

 Color of the Seed-coats of Plants 

 and the Qualities of Their Fruits." 

 This paper is really, in part, a reply to 

 certain phases of the experiments of 

 John Goss upon the same plant. 

 Knight's introductory statement, which 

 follows, is a curious reminder, in point 

 of form, of Mendel's own introduction 

 to his report upon his experiments 

 with peas nearly half a century later: 



"The numerous varieties of strictly 

 permanent habits of the pea, its annual 

 life, and the distinct character in form, 

 size and color of many of its varieties 

 induced me, many years ago, to select 

 it for the purpose of ascertaining, by 

 a long course of experiments, the effects 

 of introducing the pollen of one variety 

 into the prepared blossoms of another. 

 My chief object in these experiments, 

 was to obtain such information as 

 would enable me to calculate the prob- 



