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SCIENTIFIC NEWS. 



[Aug. 3, 1888. 



6ucketful of sand. This latter view is adhered to, and 

 the atom or ultimate particle is held to be impenetrable. 

 In the case of the mixture of water and alcohol, or water 

 and sulphuric acid, a curious phenomenon is presented. 

 Take alcohol and water, for example. Two equal 

 volumes of alcohol and water, when mixed, occupy less 

 space than when separate. If the sum of the volume of 

 the two separate liquids is 100, the volume of the 

 mixture will be only 94. In the case of the mixture of 



<SN& 



Fig. 3. — Representing 

 Volume of Unmixed 

 Alcohol and Water. 



Fig. 4. — Reduction of 

 Volume of Alcohol 

 and Water Mixture. 



sidphuric acid and water, the difference is greater. An 

 easy way to perform this experiment is to fill a narrow- 

 necked flask up to a line which may conveniently be 

 marked by a rubber band round the neck, then removing 

 one-half of the water, measuring it exactly, and replacing 

 it with a volume of alcohol exactly equal to that of the 

 water removed. It will be found that when the liquids 

 are mixed, the mixture will not fill the flask up to the 

 original mark. The only reasonable explanation of this 

 phenomenon is that the molecules of the two liquids 

 accommodate themselves to each other in such a manner 

 as to reduce the pores, and thus diminish the volume of 

 the mixture. 



THE NUMBER OF CENTENARIANS. 



WITHIN the memory of the present generation an 

 able and influential writer, Sir George Cornwall 

 Lewis — not to be confounded with G. H. Lewes — sought 

 to show that there were in modern times no authenti- 

 cated instances of persons reaching the age of one 

 hundred years. Perhaps the first fatal blow to his 

 theory was given by the well-known case of Professor 

 Chevreul, the date of whose birth has been satisfactorily 

 authenticated, and who has spent the greater part of his 

 102 years under the eye of the scientific world. 



M. Emile Lavasseur has recently made a communi- 

 cation to the Academy of Sciences on the centenarians now 

 living in France, taking his data from the census of 1886. 



He admits that there are persons of the age of one 

 hundred years, though their number is less than it is 

 popularly believed. Old men, sometimes, out of vanity, 

 represent themselves as more aged than they really are. 

 Octogenarians who have been consulted as to the age of 

 their senior relatives are led to represent them as older 

 than is really the case, having always known them 

 older than themselves. Thence spring illusions and 

 exaggerations of the number of centenarians. 



The head of the Statistical Department of Bavaria was 



the first to check over the declarations of alleged centen- 

 arians by occasion of the census of 187 1. There were 

 said to be 37, but on examining the dates of birth there 

 was found only one person, a woman, who had lived for 

 more than a century. 



About the same time a similar inquiry was made in 

 Canada, a country which had enj'03'ed for some time the 

 reputation of longevity. Mention was made of 421 

 persons said to have died at the age of 100 or upwards,, 

 but on close scrutiny only nine persons, five men and 

 four women, were found who had demonstrably lived for 

 more than a century. 



In France the first reports sent in, judging from the 

 census returns of 1886, gave the number of centenarians 

 as 184. On the first scrutiny it was found that 101 

 persons had been wrongly inserted in this category. Of 

 the 83 persons still pronounced to be centenarians, 67, 

 had no more definite evidence than the assertions of their 

 neighbours. Authentic documents, such as certificates 

 of baptism, were found only in 16 cases. Among these 

 is a man (Joseph Ribas) born at San Esteran de Litera, 

 in Spain, and baptised August 20th, 1770, and who conse- 

 quently was in 1886, n6f years. He lives, or at least 

 he was still living, at Tarbes. He was married at the age 

 of fifty, had seven children, and became a widower at lOOi 

 If this man has not appropriated the baptismal certificate 

 of an elder brother — which is improbable, since there 

 exist in France documents dating back to a time when 

 he could have no interest in exaggerating his age — he is 

 an authentic instance of an unusually advanced age. The 

 rest, 82 in number, were from 100 to 105 years ; a widow 

 was said to be 112 years old, but her age seemed very 

 doubtful. 



Women formed the majority (52, women, 37 men). 

 There were naturally few married couples, six cele- 

 bates of the male sex, and sixteen of the female, 

 twenty-three widowers, and forty-one widows. One of 

 them, aged 103, Madame Rostkowski, born Mazurkiewicz, 

 daughter of a chamberlain of Stanislas II. and sister of a 

 general of engineers, went through the Polish wars as 

 assistant surgeon-major along with her husband, who was 

 captain adjutant-major ; she had gone through twelve 

 campaigns, and had been twice wounded. She still lives, 

 on a pension of sixty francs per month allowed her by 

 the French Government. The majority of the centena- 

 rians are in a state of indigence. Seven only are in 

 easy circumstances, twenty-two in actual poverty, and 

 the remainder in a very humble position. 



There is no reason 'to believe that the number of cen- 

 tenarians in France is either increasing or decreasing, 

 and there is no evidence that in past centuries persons 

 reached a higher age than the}' do at present. For about 

 twenty years the registers of deaths give a yearly average 

 of 73 centenarians, a number probably exaggerated like 

 that in the census returns. 



According to these returns more centenarians exist in 

 the south-western departments than in the rest of France. 

 This is confirmed by the registration of deaths, since one- 

 fourth of the centenarians dead from 1866 to 1885 

 belong to six departments in the south-west. Accord- 

 ing to a table drawn up by M. Turquan, the basin of the 

 Garonne, from the Pyrennees to the Puy de Dome, 

 contains as many centenarians as all the rest of France. 

 If we, to allow for possible exaggerations, reduce the 

 number of centenarians dying yearly to 50, we find 

 that the chances of a person in the nineteenth century 

 reaching the age of 100 are 1 in 18,800. 



