372 VETERINARY LECTURES 



formulated in the laboratory. It has been observed that some 

 of these specific germs, like the germ of wheat or of other grain, 

 retain their vitality for a considerable time in a dry condition, and 

 that they are ever present with us in air, water, and food. Now, 

 if they are so ready to establish their action when cultivated in the 

 laboratory, all conditions being suitable, how does it happen that the 

 various specific diseases these germs are said to produce are not ever 

 present, and that all animal life has not been destroyed ? Probably 

 it is because, like seeds of higher organisms of every kind, the 

 surroundings must be replete and complete with every necessary 

 condition favourable to their germination and development ; or it may 

 be essential that, through some peculiarity in the atmosphere, locality, 

 food, or other influences, acting either collectively or separately, the 

 body of the patient must first be brought into such a condition that 

 the particular germ specific to the malady, which has been lying 

 latent, finds the circumstances suitable for germination and growth. 



6 1 8. Symptoms. — Tetanus in a mild form is not readily detected, 

 but in its acute stages the symptoms are more prominent. The first 

 to be noticed are that, if the animal is made to walk, it moves 

 stiffly, and with a wooden gait ; the head is extended forward, nose 

 pointed out, ears pricked out in front ; there is straddling of the hind- 

 legs, the hocks of which are turned out, and the tail is raised and 

 shaking. If the animal is in the stall, the hind-legs are placed back- 

 wards, wide apart, with the points of the hocks turned out, the tail 

 elevated and quivering, the head pulled up, and the eye very watch- 

 ful ; whilst the slightest noise seems to aggravate the symptoms. 

 On approaching the head, the animal recedes and drags the fore-feet 

 backwards, raising the head higher ; the eye-ball is drawn back into 

 the socket, and the haw (membrana nictitans) is stretched across the 

 front of the eye, giving it the peculiar appearance of a squint. The 

 latter is looked upon as a confirming symptom, yet the jaws may 

 still be slightly movable. But, as the case proceeds, the symptoms 

 become more pronounced ; the muscles of the face have a tense, 

 pinched appearance ; the nostrils are wide open, and there is foam- 



