_Smell._ Olfactory acuteness is tested by solutions of essences of varying strength, which the patient should be requested to place in order, indicating the one in which he first detects an odour. Ottolenghi has invented a graduated osmometer which is easy to use. The criminal generally shows olfactory obtuseness.
_Taste_ is tested in the same way as smell, by varying solutions of saccharine or strychnine dropped on to the patient's tongue by means of a special medicine dropper. The mouth should be rinsed out each time. Normal persons taste the bitterness of sulphate of strychnine in a solution 1:600,000; the sweetness of saccharine in a solution 1:100,000. The sense of taste is less acute in criminaloids than in normal persons, and is specially obtuse in born criminals, 33% of whom show complete obtuseness.
_Movements._ Normal individuals in a state of repose remain almost motionless, and their gestures are always appropriate. Lunatics and imbeciles have a habit of speaking and gesticulating even when they are not interrogated. Nervous diseases manifest themselves in facial contortions or slight spasmodic contractions. In melancholia and all forms of depression, the patient does not gesticulate but remains immovable like a statue with his eyes cast down. Degenerates manifest a fairly varied series of involuntary motions,--twitchings of the muscles, as in chorea, tonic and clonic convulsions and tremors. In senility, chorea, and Parkinson's disease, the tremors are incessant and continue even when the body is in a state of repose; in sclerosis, goitre, and chronic inebriety they accompany voluntary movements, and in this case they are easily detected by making the patient lift the tip of his finger to his nose or a filled glass to his lips. The nearer the hand approaches its goal, the more intense the oscillations become. Above all, the examiner should not fail to ask the patient to put out his tongue. If it protrudes on one side, it is a sign of a serious nervous alteration and nearly always denotes the beginning or remains of paralysis, or partial apoplectic strokes.
_Muscular Strength_ is measured by a common dynamometer (Fig. 38), which the patient is requested to grasp with all his might. Compressive strength is tested by compressing the oval. In order to test tractive strength, the dynamometer is fastened to a nail at the point C, and the patient pulls with all his strength at D. The effort is registered on a graduated scale and is of importance for detecting left-handedness and measuring the extraordinary force that is displayed in certain states of excitement.