The Probert Encyclopaedia of Science & Technology

HARROW

Harrows are various distinct agricultural instruments having teeth. A break harrow, usually with teeth at an angle of 80 degrees, was used for finely pulverising the soil preparing it for sowing; angular weeding harrows sometimes followed the break harrow and were designed to uproot and collect weeds, they had rearmost teeth at a more acute angle to collect the uprooted weeds; a third type of harrow consisting of a one or two frames of teeth attached by cord to a wheeled harness - and thereby applying a gentle raking action to the soil - was used for covering the sown seeds in the drill.
Research Harrow