Physiology : a manual for students and practitioners . capable ofsohition in the mucus of the Schneiderian membrane. The sub-stance must pass in a current of air through the nostrils or it is notperceived as an odor. This is accomplished by sniffing the air,and thus creating an intermitting current which is tested by theolfactory sense. In this way a trace of a gas or impalpable powdermay be detected which cannot be traced by chemical or other the substance be applied as a solution, it is not detected; thus,rose-water in a nasal douche is not noticed while the nostrils arefull of flui
Physiology : a manual for students and practitioners . capable ofsohition in the mucus of the Schneiderian membrane. The sub-stance must pass in a current of air through the nostrils or it is notperceived as an odor. This is accomplished by sniffing the air,and thus creating an intermitting current which is tested by theolfactory sense. In this way a trace of a gas or impalpable powdermay be detected which cannot be traced by chemical or other the substance be applied as a solution, it is not detected; thus,rose-water in a nasal douche is not noticed while the nostrils arefull of fluid, and yet as soon as the nostrils are free the odorappears. Where is the organ of the sense of smell ? In tlie mucous membrane of the upper part of the nasal olfactorj- nerves are the functional nerves of the sense, and arespread out in a fine network (Fig. 42) over the surface of the supe-rior or turbinated bone and upper portion of the middle turbinatedbone, and on the upper third of the septum. The nerves end in 154 THE Distribution of Nerves in the Nasal Passages: 1, olfactory bulb, with its nerves; 2, nasalbranch of the fifth pair; 3, spheno-palatine ganglion. special end-organs, known as olfactory cells, whicli lie under tlieciliated epithelium of the part. Describe the origin of the olfactory nerves. The nerves arise from a mass of gray matter lying beneath theanterior lobe of the brain upon the cribriform plate of the ethmoidbone. This is the olfactory bulb, and it is connected by theolfactory tract with the cerebrum. Is tactile sensibility a property of the olfactory nerve ? No. The lining membrane of the nasal cavity is very sensitiveto irritation, but the nasal branch of the fifth nerve and branchesfrom the spheno-palatine ganglion furnish the ordinary and tactilesense. Do the perceptions by the olfactory and by the nerves of touchresemble each other? Often they do, and some stimuli aifect both nerves. The com-mon sensibility is evoked by
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectphysiology, bookyear1
