"The President shall have Power to fill up all Vacancies that may happen during the Recess of the Senate, by granting Commissions which shall expire at the End of their next Session."
To wit, the textual authorization for the President "to fill up all vacancies that may happen during the recess of the Senate, by granting commissions which shall expire at the end of the [Senate's] next session" can't reasonably be read as permitting the President to fill up all vacancies extant when the Senate goes into recess.
Isn't the whole purpose of this provision of the Constitution to enable the President to appoint people to vacancies at a time when the Senate is unable to do so?
The Senate cannot fill vacancies when there is no quorum. So, if there is no quorum for a substantial time of nine days or more, shouldn't that qualify as a "recess"?
the period of time when the senate is not sitting in regular or extraordinary session as a branch of the Congress, or in extraordinary session for the discharge of executive functions; when its members owe no duty of attendance; when its Chamber is empty; when, because of its absence, it can not receive communications from the President or participate as a body in making appointments....Its sole purpose was to render it certain at all times there should be, whether the Senate was in session or not, an officer for every office, entitled to discharge the duties thereof.
[I]f Vacancies [in the Senate] happen by Resignation, or otherwise, during the Recess of the Legislature of any State, the Executive thereof may make temporary Appointments until the next Meeting of the Legislature, which shall then fill such Vacancies.
When vacancies happen in the representation of any State in the Senate, the executive authority of such State shall issue writs of election to fill such
vacancies: Provided, That the legislature of any State may empower the executive thereof to make temporary appointments until the people fill the vacancies by election as the legislature may direct.