LEANING TOWER OF PISA

Evening Post, Volume CIX, Issue 45, 22 February 1930, Page 20

LEANING TOWER OF PISA

SLOWLY., BUT ■ STEADILY FALLING

The leaning tower of Pisa is slowly but continually falling!. From 1919 to 1929 it baa increased, its inclination by ten millimetres, one millimetre each year, "amounting to a little "more than a-third'of 'an inch. ■"' .This, has been rigi orously ascertained in. tho last • weeks 'by tho Commission .nominated by the i Italian. Government to' study, and possibly solve forever, the age-long problem of tho equilibrium: of the beautiful tower, reports the Hew York '.'Times." Thefisaii campanile,- 180 feet High; deviates already about sixteen feet from ;the perpendicular. One foot more'and the vertical 'line. of. its -centre of gravity would fall outside its base, fcausing tb'o-.w.alls:to begh; to crumble and'fall. , At- tiio present rate of motion, this -might bo exported to happen in not-less tha. 300 years. Unluckily, there arc 'reasons: to 'fear that the gradual falling of tho tower will not: increase in arithmetical but rather in geometrical progression. ;Steps therefore must bo taken to prevent a: disaster (or even the rising of any.serious anxiety concerning, it which would deprico the world of one of its most admired buildings. -.'. .-. • ..■' "■■' '-' : The" eauso of this slow but steady' progress in the loaning of the tower of Pisa is niainly t> bo ascribed to the composition of tho ground supporting it. .The boring of this ground - and other recent.and more scientific electrical, researches have revealed that tho be soon tho spot whero, toward tho end of tho sixteenth century, Galileo Galilei took advantage of the thrusting forward of the tower to give a practical demonstration, of his principlo proclaiming the equality .of the velocity of- »H falling bodies, great and small. On tbo top floor of tho campanile are tlio lingo bells of the cathedral, seven in

number, as are the musical notes they represent. Each one of them has a names and the oldest, "La Pasquare.Cr cia," bcai engraved between the pictures of tho Virgin and of the Angel Gabriel the words: "Locteringus of Pisa mado mci in A.D. 1262.',' They are rung together only three- times si year, because it is feared that their powerful vibrations may injure the stability, of the tower. ■' .. clay and sand layers go as far down as twelve yards and that tho wator strata running through them arc two. This explains why around the base of tho tower there is always .a little pool of greenish water, into which the incredibly numerous Pisun urchins delight in throwing all kindj of iloating matter. Among all tho possible ways suggested by modern ingenuity to strengthen tho falling tower, tho best seems to be the cementing of the ground around and under it. Experiments wade on another side of the same square with pillars laden with iron weights, causing the same pressure on the ground as produced by tho campanile, namely, ten kilograms per square centimetre, havo given very encourag- ■ ing results. It is interesting to notice, just to rcaliso the miracle of all, that weight having been supported for centuries by tho weak ground underneath, thati new buildings raised in the neighbourhood never exceed the weight of one kilogramme per square centimetrie. However precarious may becomo in tho futuro tho condition of the leaning tower, of Pisa, visitors should as yet feel no hesitation about entering it and climbing its narrow, slanting staiTs. This is, on tho contrary, to bo still strongly recommended. Only from tho top of if can one fully perceive the degree of its deviation, and there can also