dissentio a te, _I dissent from you_;

secernantur a nobis, _let them be separated from us_.

4. The Preposition is freely omitted in poetry.

Ablative of Source.

215. The Ablative of Source is used with the participles natus and ortus
(in poetry also with editus, satus, and some others), to designate
_parentage_ or _station_; as,--

Jove natus, _son of Jupiter_;

summo loco natus, _high-born_ (lit. _born from a very high place_);

nobili genere ortus, _born of a noble family_.

1. Pronouns regularly (nouns rarely) take ex; as,

ex me natus, _sprung from me_.

2. To denote remoter descent, ortus ab, or oriundus (with or without ab),
is used; as,--

ab Ulixe oriundus, _descended from Ulysses_.

Ablative of Agent.

216. The Ablative accompanied by a (ab) is used with passive verbs to
denote the _personal agent_; as,--

a Caesare accusatus est, _he was arraigned by Caesar_.

1. Collective nouns referring to persons, and abstract nouns when
personified, may be construed as the personal agent. Thus:--

hostes a fortuna deserebantur, _the enemy were deserted by Fortune_;

a multitudine hostium montes tenebantur, _the mountains were held by a
multitude of the enemy_.

2. Names of animals sometimes admit the same construction. Thus:--

a canibus laniatus est, _he was torn to pieces by dogs_.

Ablative of Comparison.

217. 1. The Ablative is often used with Comparatives in the sense of
_than_; as,--

melle dulcior, _sweeter than honey_;

patria mihi vita carior est, _my country is dearer to me than life_.

2. This construction, as a rule, occurs only as a substitute for quam
(_than_) with the Nominative or Accusative. In other cases quam must be
used; as,--

tui studiosior sum quam illius, _I am fonder of you than of him_.

--Studiosior illo would have meant, _I am fonder of you than he is_.

Plus, minus, amplius, longius are often employed as the equivalents of plus
quam, minus quam, etc. Thus:--

amplius viginti urbes incenduntur, _more than twenty cities are fired_;

minus quinque milia processit, _he advanced less than five miles_.

3. Note the use of opinione with Comparatives; as,--

opinione celerius venit, _he comes more quickly than expected_ (lit.
_than opinion_).

INSTRUMENTAL USES OF THE ABLATIVE.

Ablative of Means.

218. The Ablative is used to denote _means_ or _instrument_; as,--

Alexande