KiRKPATRiCK — Charles Willoughhij, M.D. 243 



(sons) yn daughters, yt gentlemen have not, by reason of yr intemperance. 

 The case of FUixes seems to me not very difficult. Generally change of air drink 

 and diet cause ym. Ye dissolving Juices in the stomack not concocting ym right 

 at first when drink in Ireland was rare, meat ill boyled & lean, bread ill baked, 

 & beds & houses not so convenient & warm as in England, every one yt came out 

 of it had a flux, but lately very few came out of it in proportion, & those yt came, 

 took care of ymselves. They found ye drink meat and accommodation mended, 

 & to be had for money. No wonder therefore they escaped the flux, but wre 

 multitudes came from England, & are ill accommodated, ye flux is as common as 

 ever. The number of bogs drained is so very few, yt they cou'd make little 

 alteration in the air. Perhaps ye number of houses & multitude of fires might : 

 for I observe here burning ye heath on the mountains causes winds immediately 

 & sensibly alter ye weather. 



What you hint of imploying an army, in time of peace, to drain bogs, is a 

 dangerous point. It touches yr ease & pleasure ; & they had rather make a war 

 yn have yse invaded, but when all is done, this wou'd be the best use they coud be 

 put to ; & it wou'd really make ym more usefull in war, as appeared from ye 

 Eoman armys, who whilst thus imployed conquered ye world, but came to nothing, 

 when they became too gentile to work. 



You say in the beginning of your paper yt ye new built houses in Dublin were 

 filled with inhabitants, as soon as finished, without any decrease of Rent. Yt is 

 a very great mistake, for tiie rents in Castle street skinner row &c fell very near 

 half of what they had been, generally a third ; & I am of opinion, ye number of 

 inhabitants did no way increase in proportion to ye buildings. 



In May 1690 ye minister of Dublin, by order, returned ye number of protestant 

 men in the city and libertys, from 16 to 80 & they amounted to 8300, & some odd 

 persons. Consider how that will agree with Sir Wm Pettys proportions. 



Worthy sr I am ashamed to have so little to add to your observations, & yet 

 to have been so tedious : I hope you will take these in good part, & believe yt 

 I am 



Your affectionate humble sert. 



Will : Derry. 

 Endorsed To Dr Willoughby (May) 19 1691. 



The whole subject of " Political Arithmetic," or, as we should now call 

 it, " Vital Statistics," was at that time exciting much interest on account 

 of the wrioings of Sir William Petty and Captain John Graunt. Willoughby's 

 paper does not throw much new light on the subject ; but King's letter is 

 interesting, and it shows how two hundred and thirty years ago the 

 suspicions of the country people made the collection of reliable statistical 

 information as difficult as it is at present. 



/■ The three following letters, written by Willoughby to King, are preserved 

 among the King correspondence in Trinity College, and have not been hitherto 

 published. The first is chiefly of medical interest, being the considered 

 opinion of a physician on the diagnosis and treatment of a patient's sickness, 



