A device and method for dispensing precise amounts of dry particulate matter, such as agricultural chemicals, directly into a liquid carrier stream, such as a flow of water, and a method of employing such a device to distribute chemicals. The device includes a bin for holding a quantity of particulate matter, a conduit for transporting a stream of liquid carrier, and a meter at the bottom of the bin for controllably releasing a desired amount of the particulate matter from the bin into the conduit while disallowing entry of the liquid carrier to the bin. The bin, conduit and meter are all mounted upon a portable structure for transportation with particulate matter in the bin. The meter includes a multi-vaned rotor turned by a controlled motor, and defines discrete pockets of known volume. The operator simply connects the device to a flow of water and keys into the controller an amount of material to be released. The rotor releases the material into a chamber under vacuum pressure generated by a venturi, through a check valve, and into an eductor. Agricultural chemicals may be advantageously distributed to end users in particulate form, to be mixed with a liquid carrier at the work site, without possibly harmful exposure to chemical dust and fumes.