260 



♦ KNOWLEDGE 



[Sept. 26, 1884. 



of trees, and seeming to be still alive and talking with each 

 other, in the same situation in which death had overtaken 

 them. 



The observations which precede seem to us to furnish 

 some useful information in regard to some points of the 

 question. Thus, a perception of danger is not necessary to 

 explain the influence exerted upon the subject. The case 

 of the soldier observed at Beaumont, near Sedan, seems 

 to be demonstrative. He was not conscious of danger, by 

 reason of the quick and unforeseen action of the bullet. 

 This cause most certainly cannot be invoked in case of 

 death through lightning. It is perfectly demonstrated by 

 numerous observations that the subjects thus struck have 

 not and cannot have any apprehension of their imminent 

 danger. The person who is struck by lightning not only 

 does not hear the noise of the thunder, the propagation of 

 which is relatively slow, but he has not even any percep- 

 tion, any warning of the flash, whose rapidity is proverbial. 

 Death is instantaneous, and the subject has not expe- 

 rienced the moral influence that results from a perception 

 of danger. We have particularly related the cases that 

 comprise animals (obs. 7 and 10). These could not have had 

 any such apprehensions. It is remarkable to see that all 

 the dogs were struck, and that all preserved their alti- 

 tude in the occurrence at Chateauneuf, while the number 

 of human victims was proportionately much less. None 

 of these latter, moreover, preserved the attitude that be 

 had at the moment of death. In obs. 6 a man preserves 

 his position and remains seated near four dead horses that 

 did not maintain their attitude. In obs. 1 we see that all 

 the individuals exposed to the action were kUled, and all 

 (to the number of eight) preserved tbeir attitude. In the 

 second case four out of ten were struck, and the six others 

 do not appear to have been influenced by the electric fluid. 

 In short, all those that were struck dead preserved the 

 last attitude of life. 



Oases of lightning stroke are unfortunately quite 

 numerous, but the number of those in which a preserva- 

 tion of the attitude has been observed is relatively limited. 

 Although there are no comparative figures upon which an 

 exact proportion can be established with certainty, it 

 nevertheless appears that they are more frequent after 

 lightning stroke than after other modes of sudden death. 



Let us further remark that in cases of death by light- 

 ning, with a preservation of the attitude, it has been found 

 that no external lesion exists (obs. 11) upon the body of 

 the victim, and no autopsy has shown what point was thus 

 influenced without any apparent contact. Perhaps no 

 peculiar alteration could have been found in the essential 

 organs of life ; and it is especially in such cases that we 

 may employ the expression sideration in all its accepta- 

 tions. 



The peculiar circumstances that accompany death by 

 lightning may acquire (as they have done) a certain im- 

 portance from a medico-legal point of view. But I have 

 not to concern myself with that here, my only object 

 having been to point out a few interesting facts, whence 

 we may draw some useful data for the study and solution 

 of this question of post-mortem preservation of the last 

 attitude of life. — Dr. J. Rouyer, in La Nature. 



Ajj illustration of the way in which a coefficient like 0000006, the 

 coefficient of expansion of steel, may become a big thing with a 

 few degrees and long lengths, has been seen on the new Midland 

 line between Irchester and Shambrook, recently opened for goods 

 traffic. The rails were laid during winter time, and insufficietit 

 room was left for expansion ; consequently the summer heat lately 

 expanded the rails to sneh an extent that the road burst out of line. 

 Traffic had to be at once stopped, and the permanent way altered 

 and properly spaced. 



THE INTERNATIONAL HEALTH 

 EXHIBITION. 



XVir.— THE SOFTENING OF WATER— (coniitiued). 



IN our last communication we pointed out that although 

 very soft water is in many instances undesirable, it is 

 of the first importance to the vast majority of manufacturers 

 and engineers. The uses to which softened water can be 

 put are so varied and extensive that the subject has claimed 

 and received the attention of many competent and active 

 workers. We have shown that in order to be of practical 

 value, softened water ought to be freed from all mechanical 

 as well as dissolved impurities, and that these results are to 

 be attained not only by a successful system of straining, but 

 by chemical means in addition. 



In 1781, a paper was read to the Literary and Philoso- 

 phical Society of Manchester by Thomas Henry, F.R.S., in 

 which he gave an account of his process for purifying 

 sea-water by the use of quicklime ; he referred also to the 

 value of that reagent in the preservation of common water. 

 It was not until 1838, however, that a patent process for 

 the softening of water was instituted. Muriate of zinc, 

 subsequently acted upon by salts of soda, was employed 

 to precipitate the impurities from water. 



Later on, in 1841, Dr. Thomas Clark, the Professor of 

 Chemistry at the University of Aberdeen, patented the 

 well-known process with which his name will always be 

 associated. He published a complete description of it in 

 the Journal of the Society of Arts on the 16th May, 1856. 

 Clark's process takes advantage of the solubility and in- 

 solubility of lime in the two conditions in which it becomes 

 associated with carbonic acid sras. 



The Porier-Clark Apparatus. In operation at the International 

 Health Exhibition (400 gallons per hotir). 



The vast formations of limestone, chalk, and other cal- 

 careous rocks of hard water districts consists of lime in the 

 form of a carbonate. The percolation of water, such as 

 ordinary rain-water charged with carbonic acid gas through 

 calcareous strata, results in the removal of the carbonate 

 by its solution as a bicarbonate, and gives rise to a hard 

 water. To remove that hardness it is obvious that a 

 separation of this extra quantity of carbonic acid would 

 leave the lime once more in the character of an insoluble 

 carbonate, and this is exactly what happens when lime 

 water is used. 



