Caesar, Dē Bellō Gallicō 6.27
Sunt item, quae appellantur alcēs. hārum est consimilis caprīs figūra et varietās pellium, sed magnitūdine paulō antecēdunt mutilaeque sunt cornibus et crūra sine nōdīs articulīsque habent neque quiētis causā prōcumbunt neque, sī quō adflictae cāsū concidērunt, ērigere sēsē aut sublevāre possunt. hīs sunt arborēs prō cubīlibus: ad eās sē applicant atque ita paulum modo reclīnātae quiētem capiunt. quārum ex vestīgiīs cum est animadversum ā vēnātōribus quō sē recipere consuērint, omnēs eō locō aut ab rādīcibus subruunt aut accīdunt arborēs, tantum ut summa speciēs eārum stantium relinquātur. hūc cum sē consuētūdine reclīnāvērunt, infirmās arborēs pondere adflīgunt atque ūnā ipsae concidunt.
There are also animals called elk. Their shape and their dappled hides are like those of roe deer, but they are slightly bigger and are without horns. They have legs without tendons or joints, and do not lie down to sleep, nor, if they have accidentally fallen down, are they able to set themselves straight or raise themselves up. Trees serve them as beds: they lean against them and thus, at just a slight incline, they take their rest. When hunters have noticed by their tracks where they usually go, they either undermine the roots of all the trees in that spot or they cut them so that the upper trunks of the trees seem to be left standing. When the elk have leaned against the trees as usual, they knock the weak trees over with their weight and they themselves collapse along with them.
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