Adapted from The Effects of Cross & Self-Fertilisation in the Vegetable Kingdom by Charles Darwin (1876)

As it is impossible to exclude such minute pollen-carrying insects as Thrips, flowers which it was intended to fertilise with their own pollen may sometimes have been afterwards crossed with pollen brought by these insects from another flower on the same plant; but as we shall hereafter see, a cross of this kind does not produce any effect, or at most only a slight one. When two or more plants were placed near one another under the same net, as was often done, there is some real though not great danger of the flowers which were believed to be self-fertilised being afterwards crossed with pollen brought by Thrips from a distinct plant. I have said that the danger is not great because I have often found that plants which are self-sterile, unless aided by insects, remained sterile when several plants of the same species were placed under the same net. If, however, the flowers which had been presumably self-fertilised by me were in any case afterwards crossed by Thrips with pollen brought from a distinct plant, crossed seedlings would have been included amongst the self-fertilised; but it should be especially observed that this occurrence would tend to diminish and not to increase any superiority in average height, fertility, etc., of the crossed over the self-fertilised plants.

As the flowers which were crossed were never castrated, it is probable or even almost certain that I sometimes failed to cross-fertilise them effectually, and that they were afterwards spontaneously self-fertilised. This would have been most likely to occur with dichogamous species, for without much care it is not easy to perceive whether their stigmas are ready to be fertilised when the anthers open. But in all cases, as the flowers were protected from wind, rain, and the access of insects, any pollen placed by me on the stigmatic surface whilst it was immature, would generally have remained there until the stigma was mature; and the flowers would then have been crossed as was intended. Nevertheless, it is highly probable that self-fertilised seedlings have sometimes by this means got included amongst the crossed seedlings. The effect would be, as in the former case, not to exaggerate but to diminish any average superiority of the crossed over the self-fertilised plants.

Errors arising from the two causes just named, and from others,—such as some of the seeds not having been thoroughly ripened, though care was taken to avoid this error—the sickness or unperceived injury of any of the plants,—will have been to a large extent eliminated, in those cases in which many crossed and self-fertilised plants were measured and an average struck. Some of these causes of error will also have been eliminated by the seeds having been allowed to germinate on bare damp sand, and being planted in pairs; for it is not likely that ill-matured and well-matured, or diseased and healthy seeds, would germinate at exactly the same time. The same result will have been gained in the several cases in which only a few of the tallest, finest, and healthiest plants on each side of the pots were measured.

Kolreuter and Gartner have proved that with some plants several, even as many as from fifty to sixty, pollen-grains are necessary for the fertilisation of all the ovules in the ovarium. Naudin also found in the case of Mirabilis that if only one or two of its very large pollen-grains were placed on the stigma, the plants raised from such seeds were dwarfed. I was therefore careful to give an amply sufficient supply of pollen, and generally covered the stigma with it; but I did not take any special pains to place exactly the same amount on the stigmas of the self-fertilised and crossed flowers. After having acted in this manner during two seasons, I remembered that Gartner thought, though without any direct evidence, that an excess of pollen was perhaps injurious. It was therefore necessary to ascertain whether the fertility of the flowers was affected by applying a rather small and an extremely large quantity of pollen to the stigma. Accordingly a very small mass of pollen-grains was placed on one side of the large stigma in sixty-four flowers of Ipomoea purpurea, and a great mass of pollen over the whole surface of the stigma in sixty-four other flowers. In order to vary the experiment, half the flowers of both lots were on plants produced from self-fertilised seeds, and the other half on plants from crossed seeds. The sixty-four flowers with an excess of pollen yielded sixty-one capsules; and excluding four capsules, each of which contained only a single poor seed, the remainder contained on an average 5.07 seeds per capsule. The sixty-four flowers with only a little pollen placed on one side of the stigma yielded sixty-three capsules, and excluding one from the same cause as before, the remainder contained on an average 5.129 seeds. So that the flowers fertilised with little pollen yielded rather more capsules and seeds than did those fertilised with an excess; but the difference is too slight to be of any significance. On the other hand, the seeds produced by the flowers with an excess of pollen were a little heavier of the two; for 170 of them weighed 79.67 grains, whilst 170 seeds from the flowers with very little pollen weighed 79.20 grains. Both lots of seeds having been placed on damp sand presented no difference in their rate of germination. We may therefore conclude that my experiments were not affected by any slight difference in the amount of pollen used; a sufficiency having been employed in all cases.

Passage 1 is adapted from Emma Hart Willard, "Improving Female Education." Originally published in 1819.

If the improvement of the American female character, and that alone, could be affected by public liberality, employed in giving better means of instruction; such improvement of one half of society, and that half, which barbarous and despotic nations have ever degraded, would of itself be an object, worthy of the most liberal government on earth; but if the female character be raised, it must inevitably raise that of the other sex; and thus does the plan proposed, offer, as the object of legislative bounty, to elevate the whole character of the community.

As evidence that this statement does not exaggerate the female influence in society, our sex  need but be considered, in the single relation of mothers. In this character, we have the charge of the whole mass of individuals, who are to compose the succeeding generation; during that period of youth, when the pliant mind takes any direction, to which it is steadily guided by a forming hand. How important a power is given by this charge! yet, little do too many of my sex know how, either to appreciate or improve it. Unprovided with the means of acquiring that knowledge, which flows liberally to the other sex- having our time of education devoted to frivolous acquirements, how should we understand the nature of the mind, so as to be aware of the importance of those early impressions, which we make upon the minds of our children? -or how should we be able to form enlarged and correct views, either of the character, to which we ought to mold them, or of the means most proper to form them aright?

Considered in this point of view, were the interests of male education alone to be consulted, that of females becomes of sufficient importance to engage the public attention. Would we rear the human plant to its perfection, we must first fertilize the soil which produces it. If it acquire its first bent and texture upon a barren plain, it will avail comparatively little, should it be afterwards transplanted to a garden.

Passage 2 is adapted from Benjamin Rush, "Thoughts upon Female Education". Originally published 1787.

A philosopher once said, "let me make all the ballads of a country and I care not who makes its laws." He might with more propriety have said, let the ladies of a country be educated properly, and they will not only make and administer its laws, but form its manners and character. It would require a lively imagination to describe, or even to comprehend, the happiness of a country where knowledge and virtue were generally diffused among the female sex. Our young men would then be restrained from vice by the terror of being banished from their company. The loud laugh and the malignant smile, at the expense of innocence or of personal infirmities– the feats of successful mimicry and the low priced wit which is borrowed from a misapplication of scripture phrases– would no more be considered as recommendations to the society of the ladies. A double-entendre in their presence would then exclude a gentleman forever from the company of both sexes and probably oblige him to seek an asylum from contempt in a foreign country.

If I am wrong in those opinions in which I have taken the liberty of departing from the general and fashionable habits of thinking I am sure you will discover and pardon my mistakes. But if I am right, I am equally sure you will adopt my opinions for to enlightened minds truth is alike acceptable, whether it comes from the lips of age or the hand of antiquity or whether it be obtruded by a person who has no other claim to attention than a desire of adding to the stock of human happiness.

To you, young ladies, an important problem is committed for solution: whether our present plan of education be a wise one and whether it be calculated to prepare you for the duties of social and domestic life. I know that the elevation of the female mind, by means of moral, physical, and religious truth, is considered by some men as unfriendly to the domestic character of a woman. But this is the prejudice of little minds and springs from the same spirit which opposes the general diffusion of knowledge among the citizens of our republics.If men believe that ignorance is favorable to the government of the female sex, they are certainly deceived, for a weak and ignorant woman will always be governed with the greatest difficulty. It  will be in your power ladies, to correct the mistakes and practice of our sex upon these subjects by demonstrating that the female temper can only be governed by reason and that the cultivation of reason in women is alike friendly to the order of nature and to private as well as public happiness.