he said and in the front of the brain is the placenta of the two papillary appendages by which the sense of smell is produced. in the middle of the front of the brain are two appendages similar to the nipples of the breast and they are the organ of smell as we will explain later. their mass is medium in hardness and softness between the brain and the nerve so they are softer than the nerve and harder than the brain. therefore their consistency is close to that of the spinal cord and slightly more inclined to hardness. they were placed in the front of the brain so that its moisture would be nourishment for them through moisture so that they would not be exposed to dryness that would reach them. they were placed in the middle between the right and left of this front and because this place is the moistest part of the front. the organ of smell was required to be very soft because its perceptible part is the quality that attracts in the inhaled air and all of that is due to its weakness. what is very receptive is only affected by it and it is only like that if it is very soft so that it is affected by stimuli even if they are very weak. and allah is the grantor of success.
قوله وفي مقدم الدماغ منبت الزائدتين الحلميتين اللتين يكون بهما يكون الشم، في وسط مقدم الدماغ من قدام زائدتان شبيهتان بحلمتي الثدي وهما الآلة في الشم على ما نبينه بعد، وجرمها متوسط في الصلابة واللين بين الدماغ والعصب فهما ألين من العصب وأصلب من الدماغ، فلذلك قوامهما قريب من قوام النخاع وأميل منه إلى الصلابة قليلا وإنما جعلتا في مقدم الدماغ لتكون رطوبته غذاء لهما بالنداوة فلا يعرض لهما جفاف يصلهما وإنما جعلا في وسط ما بين يمين هذا المقدم ويساره ولأن هذا الموضع أرطب أجزاء المقدم، وإنما احتيج أن تكون آلة الشم شديدة اللين لأن محسوسها هو الكيفية التي تجذب في الهواء المستنشق وجميع ذلك الأجل ضعفه إنما ينفعل عنه ما كان شديد القبول جدا، وإنما يكون كذلك إذا كان شديد اللين جدا حتى ينفعل عن المؤثرات وإن ضعفت جدا. والله ولي التوفيق.