274 CLINICAL VETERINARY MEDICINE AND SURGERY. 



In man the disease is usually announced by palpitation, which 

 occurs suddenly after a physical or moral shock, accident, violent 

 emotion, fright, or exhausting work, though the onset may be insidious, 

 and aggravation gradual. The heart-beats are sudden, and so violent 

 as to be visible over a large surface of the chest or even over the 

 whole body. On auscultation the normal heart-sounds are magni- 

 fied, and have a metallic ring, or are accompanied by murmurs, 

 the position and intensity of which vary, but are most commonl}^ soft 

 and systolic. The radial pulse is generally feeble, sometimes arhyth- 

 mic ; in certain cases it cannot be counted owing to its frequency ; 

 on the other hand, it may also preserve its normal character for a long 

 time. The carotids beat strongly, showing bounding movements, 

 resembling that " dancing of the arteries " seen in certain heart dis- 

 eases. Auscultation with the stethoscope sometimes detects soft or 

 rough murmurs. The superficial veins, those of the limbs, and the 

 jugulars more especially are large and distended. Both jugulars show 

 strong pulsation. 



Hypertrophy of the thyroid gland is sometimes uniform, extending 

 equally to both lobes ; sometimes it is more pronounced in one than in 

 the other. Goitre seldom appears rapidly. In most cases the gland 

 gradually increases in size, remaining somewhat elastic, soft, and 

 moveable under the skin. It is very vascular, and on auscultation 

 sometimes reveals an arterial murmur isochronous with the beating of 

 the heart. In time it may undergo hardening. 



Exophthalmia — that is, excessive prominence of the globes of the 

 eyes — is usually equally marked in both eyes. It may even develop 

 sufficiently to prevent the eyelids closing, or to threaten displacement 

 of the eyes ; this accident has indeed been seen. In other cases dis- 

 placement may be very slight, or fail to occur. In addition to undue 

 prominence of the eye rupture of the cornea is sometimes seen ; the 

 animal's gaze becomes fixed, tears escape over the face, and the 

 sclerotic is hypersemic. The pupil is usually normal ; sometimes, how- 

 ever, it is dilated or contracted. In most patients the chambers of the 

 eye remain intact and vision is unaffected, but some show dilatation of 

 the retinal vessels, myopia, or presbyopia. 



To these three symptoms must be added trembling, an almost 

 always constant sign, which is no less important than the preceding. 

 This trembling is sometimes limited to the limbs, in the upper parts of 

 which it is particularly marked. Sometimes it is general, all the 

 muscles showing fibrillary movements. 



Various secondary disturbances are seen. Appetite is lost ; diges- 

 tion is bad ; attacks of diarrhoea occur ; bodily condition and strength 



