qui interimebant eum." Other
examples of a questionable or improper use of the progressive form may
occasionally be found in good authors; as, "A promising boy of six years of
age, _was missing_ by his parents."--_Whittier, Stranger in Lowell_, p.
100. _Missing, wanting_, and _willing_, after the verb to be, are commonly
reckoned participial _adjectives_; but here "_was missing_" is made a
passive verb, equivalent to _was missed_, which, perhaps, would better
express the meaning. _To miss_, to perceive the absence of, is such an act
of the mind, as seems unsuited to the compound form, _to be missing_; and,
if we cannot say, "The mother _was missing_ her son," I think we ought not
to use the same form passively, as above.

[266] Some grammarians, contrary to the common opinion, suppose the verbs
here spoken of, to have, not a _passive_, but a _neuter_ signification.
Thus, Joseph Guy, Jun., of London: "Active verbs often take a _neuter_
sense; as, A house is building; here, is _building_ is used in a _neuter_
signification, because it has no object after it. By this rule are
explained such sentences as, Application is wanting; The grammar is
printing; The lottery is drawing; It is flying, &c."--_Guy's English
Gram._, p. 21. "_Neuter_," here, as in many other places, is meant to
include the _active-intransitives_. "_Is flying_" is of this class; and
"_is wanting_," corresponding to the Latin _caret_, appears to be neuter;
hut the rest seem rather to be passives. Tried, however, by the usual
criterion,--the naming of the "_agent_" which, it is said, "a verb passive
necessarily implies,"--what may at first seem progressive passives, may not
always be found such. "_Most_ verbs signifying _action_" says Dr. Johnson,
"may likewise signify _condition_, or _habit_, and become _neuters_, [i. e.
_active-intransitives_;] as _I love_, I am in love; _I strike_, I am now
striking."--_Gram. before Quarto Dict._, p. 7. So _sell, form, make_, and
many others, usually transitive, have sometimes an active-intransitive
sense which nearly approaches the passive, and of which _are selling, is
forming, are making_, and the like, may be only equivalent expressions. For
example: "It is cold, and ice _forms_ rapidly--is _forming_ rapidly--or _is
formed_ rapidly."--Here, with little difference of meaning, is the
appearance of both voices, the Active and the Passive; while "_is
forming_," which some will have for an example of "the _Middle_ voice," m