The expectations of Life are thus calculated by De Moivre--Subtract the age of the person from 86, half the remainder will be the expectation of that Life.
[22] See the history of a case of Spectacles, &c. in page 61 of Dr. KITCHINER'S _Practical Observations on Telescopes, Opera Glasses, &c._--Third Edition.
[23] "In proportion as the powers of the Stomach are weak, so ought we to diminish the quantity of our food, and take care that it be as nutritive, and as easy of digestion as possible."--ABERNETHY'S _Surgical Observations_, p. 67.
[24] "Nothing is a greater Enemy to feeble life, than laying aside old habits--or leaving a climate, or place, to which one has been long accustomed: the irritation occasioned by such changes is highly prejudicial.
"Even pernicious habits, insalubrious air, &c. must be abandoned with great caution--or we shall thereby hasten the end of our Patient."--STRUVE'S _Asthenology_, p. 398.
[25] "Those who have lived longest, have been persons without either Avarice or Ambition, enjoying that tranquillity of Soul, which is the source of the happiness and health of our early days--and strangers to those torments of mind which usually accompany more advanced years, and by which the Body is wasted and consumed."--_Code of Health_, vol. i. p. 60-63, &c.
"In the return made by Dr. ROBERTSON, (and published by Sir JOHN SINCLAIR, in the 164th page of the second volume of the Appendix to his Code of Health,) from Greenwich Hospital, of 2410 In-Pensioners, ninety-six--_i. e._ about one-twenty-fifth are beyond eighty--thirteen beyond ninety--and one beyond one hundred. They almost all used _Tobacco_--and most of them acknowledged the habit of _Drinking_ freely. Some of them had _no teeth_ for twenty years--and fourteen only had good ones--one who was one hundred and thirteen years old, had lost all his Teeth upwards of thirty years.
"The organ of _Vision_ was impaired in about one-half--that of _Hearing_ in only one-fifth: this may be accounted for--the _Eye_ is a more delicate organ than the _Ear_--and the least deterioration of its action is more immediately observed.--Of the _ninety-six_ they almost all had been married, and _four_ of them after eighty years of age--only nine were Batchelors--this is a strong argument in favour of Matrimony.