Book,  Paragraph

 1   I,  15|       and it is not an organ useful for generation, for it is
 2   I,  18|      is either of useless or useful nutriment; by "useless"
 3   I,  18|  much of it is consumed; by "useful" I mean the opposite. Now
 4   I,  18|    Semen, then, is part of a useful secretion. But the most
 5   I,  18|      secretion. But the most useful is the last and that from
 6   I,  18|   also is a secretion of the useful nutriment, an indication
 7   I,  18|  that of the liquid; for the useful part of the nutriment we
 8   I,  18|  removal of the secretion is useful; now the discharge of the
 9   I,  18|      semen is a secretion of useful nutriment, and that in its
10  II,  6 |     generated); thirdly, the useful, that is to say what the
11  II,  6 |    possible to make anything useful. Now in a household the
12  II,  7 |    from birth when the parts useful for union are imperfect,
13 III,  10|     other kinds, for this is useful for their work, and they
14  IV,  1 |   stage is abundant, but the useful product derived from it
15  IV,  8 | viviparous animals, becoming useful for the time of birth. For
16  IV,  8 |  month and only then becomes useful. That it is only concocted
17  IV,  8 | season that the milk becomes useful.~The milk collects in the
18  IV,  8 |   same time the milk becomes useful for the nourishment of the