From left to right (Choukhadar, Silakhtar Agha, Peik, Solak)
These were the senior of all the officers in the Janissary Corps. They were sometimes referred to as the Chief Sergeant and were also the Commander of the Fifth Squadron. The Bashchavoush would cover for the Kethudas (or Kahia Bey) in his absence but should not be confused witht the Chavoush Bashis (the Chief of the Sultan's Bodyguard) even though they did, later, become Chief Sergeants in the Janissary Corps.
Orta Chavoushou (Sergeant of the Janissaries)
These Sergeants were under the command of the Chief
Sergeant and were responsible for relaying commands to the other ranks.
They were sometimes called Middle Sergeants - there were three ranks of
sergeants: Minor, Middle and Chief Sergeants.
Kapidjibashi (Head of the Palace Doorkeepers)
This man was the senior doorkeeper in the Palace.
When foreign ambassadors came, it was the duty of the Kapidjibashi to
lead them into the presence of the Sultan. There were four Head Doorkeepers
in the Palace and their superior was a General. In later years their numbers
increased.
Koul Kethudas (General of the Boulouk Janissaries)
He was assistant to the Commander-in-Chief of the
Janissary Corps. Originally he was lower in rank than the Chief of Sekbans
but, in later years, they were demoted below the Koul Kethudas. Administration
of the Corps was his particular responsibility – promotions, appointments
and dismissals being executed by him. The post disappeared when the Janissary
Corps was abolished in 1826.