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Show ~~4 Additional Notes. ·that is they will require as much time, as tho e new sh~ots from the lopped trunk would require, before ~hey produce frutt. It should thence ue inquired, wheu grafted fnut trees are purchased, whether the scions were taken from bearino· branches, or from the young shoots of a lopped trunk; as the latter, [ believ.e, .•~re gene:ally sold, as they appear stronger plants. Thi ~reater stmihtu.cle of" the progeny to the parent in solita1:y repro~uclwn mu t certalllly ~ak c them more liable to hereditary diseases, 1f such have been. aC(flli red by the parent from unf:iendly climate or bad nourishment, or accid ental injury. . In respect to the sexual progeny of vegetables tt ha long been thou<Tht, that a change of seed or of situation is iu process of time necessary to prevent their degeneracy; but it is now believed, that it i. only cban<Tino· for seed of a SU))erior quality, that will better the b b . • product. At tl;e same time it may be probably useful occasionally to intermix seeds from different situations together; as the anther-dust is 1i;t!Jle to pass from one plant to anothe'r in its vicinity; and by these means the new seeds or plants may be amended, like the mar:- 1·iao·es of animals into ditf'ercnt families. b As the sexual progeny of vegetables are thus less liable to heredi-tary di eases than the solitary progenies; so it is reasonable to conclude, that the sexual progenies of animals may be less liable to h ereditary diseases, if the marriages are into different families, than if into the same family; this has long been supposed to be true, by those who breed animals for sale; since if the male and female be of different temperaments, as the ·e arc extremes of the animal system, they may counteract each other; and certainly where both parents are of families, which are afflicted with the same hereditary disease, it is n1ore likely to descend to their posterity. The hereditary diseases of this country have many of them been the consequence of drinking much fermented or spirituous liquor; as the gout always, most kinds of dropsy, and, I believe, epilepsy, and insanity. But another material, whieh is liable to produce diseases in its immoderate use, I believe to be comm~n salt; the sea-scurvy is evidently caused by it in long voyages; and I suspect the scrofula, and consumption, to arise in the young· progeny from the debility of llereditary Diseases. ·t he lym· p· haticf' an.d ven. ous absorption produced in the t b 1 · par en y t 11s mnutntwus os d. e stunulus. The I)Ctechi"='"' and v1'b·Ic es m· th e sea-s cur~y and occasiOnal lucmorrhages evince the defect of venous ab-sorptiOn ; the ~ccas ional h~moptoe at the commencement of pulmo~ n.ary consumption, ~ee ms al~o to arise from defect of venous absorptiOn} and the scrofula, wh1ch arises from the inactivity of the 1 mphattc a~sorbcnt sys~cm, freque1~tly exists along with pulmonar~ as well as With mcsentenc consumptiOn. A tendency to these diseases is certainly hereditary, though perhaps not the diseases themselves· thus a les qua11tity of ale, cycler, wine, or spirit, will induce the <TO~t and ~lropsy in tl~o c co~stitutions, whose parents have been int~mperate 111 the use of those liquors; as I have more than once had occasion to observe. Fi.nally the art to improve the sexual progeny of either vegetables or ammals must consist in choo ing the most perfect of both sexes, that is the most beautiful ia respect to the body, and the most ingenious in resp ect to the mind; but where one sex is given, whether male or female, to improve a progeny from that person may consist in choosing a partner of a contrary temperament. As many families become gradually extinct by hereditary diseases, as by scrofula, consumption, epilepsy, mania, it is often hazardous to marry an heiress, as she is not unfrequently the last of a diseased family. |