if there is a well-known mold that does not vary, it is permissible, just as if the measurement unit were well-known. If he stipulates it by length, width, and thickness, it is permissible. It is not sufficient to observe the mold for making bricks if it is not well-known, because there is uncertainty (gharar) in it. The mold might be destroyed, rendering the contract invalid, just as if he paid in advance for a specific unit of measure.
Section: It is permissible to hire for construction, and it may be stipulated by duration or by the task. If he stipulates it by the task, it is necessary to know the site, because it also varies according to the proximity of water and the ease of the soil. It is necessary to mention the length, width, and thickness, as well as the materials for construction, such as mud bricks and mud, or stone and mud, or lime (shid) and baked bricks, or other than that. Ibn Abi Musa said: If he hires him to build a thousand bricks in his wall, or hires him to build for him in it for a day, and he performs what he was hired for, then the wall collapses, he is entitled to his wage, because he fulfilled the work. If he says: "Build this wall up to ten cubits for me," and he raises part of it, then it collapses, he is obligated to rebuild what collapsed and to complete the measured amount upon which the hiring contract was based. This applies if the collapse in the first instance was not due to something on the part of the worker. As for if he was negligent, or built it loosely, or the like, and it collapsed, he is obligated to rebuild it and pay for what was damaged from it.
Section: It is permissible to hire for plastering roofs and walls. It is not permissible to hire for a specific task, because the mud varies; some of it is thin and some is thick, and the surface of the roof varies, some of it being high and some low, and likewise the walls; therefore, it is not permissible except based on a duration.
Section: It is permissible to hire a scribe to copy for him books of jurisprudence (fiqh), tradition (hadith), permissible poetry, or official records. This was explicitly stated in the narration of Muthanna ibn Jami', who asked him about copying hadith
(15) Al-shid: That with which a wall is coated, such as plaster and the like. (16) In the original: "wall". (17) Omitted from the original. (18) In B: "roofs". (19) In the original: "there are high and low parts in it".
