Fluid circulation

A method for use in fluid jetting, the method comprising:

• delivering a first portion of a fluid at a controlled flow rate along a first flow path from a first container to a second container, the first portion of the fluid in the first flow path passing by a second flow path in a printhead along a first direction, the second flow path fluidically connecting the first flow path to a nozzle such that a second portion of the fluid passing through the first flow path being is delivered through the second flow path to the nozzle when the nozzle is ejecting the fluid delivered from the first container;
• and
• delivering a third portion of the fluid at a controlled flow rate along a third flow path from the second container to the first container, the third portion of the fluid in the third flow path passing by the second flow path in the printhead along a second direction opposite to the first direction, the second flow path fluidically connecting the second flow path to the nozzle such that a fourth portion of the fluid passing through the third flow path is delivered through the second flow path to the nozzle when the nozzle is ejecting the fluid delivered from the second container.

(canceled)

A method for use in fluid jetting, the method comprising:

• flowing a fluid at a controlled flow rate from a first container through a flow path in a first flow direction, the flow path configured such that a first portion of the fluid flows from the first container to a second container and a second portion of the fluid flows from the first container to a nozzle when the nozzle is ejecting the fluid delivered from the first container;
• and
• reversing a direction of flow of the fluid in the flow path such that the fluid flows from the second container through the flow path in a second flow direction opposite the first flow direction, the flow path configured such that a first portion of the fluid flows from the second container to the first container and a second portion of the fluid flows from the second container to a nozzle when the nozzle is ejecting the fluid delivered from the second container.