[Pramāṇa](https://indike.org/pramana/) › [Physical](https://indike.org/pramana/inp) › [Artefacts](https://indike.org/pramana/inp.artefact) › [Indian Museum, Kolkata](https://indike.org/pramana/inp.artefact.im) › JANTRAI / Tool # JANTRAI / Tool JANTRAI / Tool: It is a rectangular shaped iron plate contains forty two perforations. - **Kind:** artefact --- Source: [https://indike.org/pramana/inp.artefact.im.2279](https://indike.org/pramana/inp.artefact.im.2279) · Pramāṇa