( ^45 ) 



The same aj)peare(l, slill more distiiu'lly, soiilli Drilarlem, thi-oiiiili llie 

 infliiciK'C, wliicli (lie e.\leiisi\e Haarlemmermeer |k)1(I(m-, willi ils (ni(lyiiij>- 

 polders, eastward, has on it ; (he summer lexel of (hose |)olders, 

 which together covei- 42()()() H. A., being' aixnit 5 M. or more under A.P. 



At Aerdenhont a well, 32 M. -! A.P. deep, showed a level of 

 0.52 M. + A.P. on May 5ti' HIO:]. We may admi( (hat at (he(ime 

 the level of the other wells was being ascertained, it must have 

 been here abont 0.40 M. -)- A.P. This well is HfiOO M. from the 

 Haarlemmermeer polder ami only 350 JM. from the Veen|»older 

 (Summer-Level -f- 0.75 M.). A well at Heemstede, oji Kennemeroord, 

 deep only 26.3 M. -!- A.P. ; but smdv down into the gravelly sand, 

 had on June 2"^^ 1903 a level of 0.575 M. -f A.P. That well, 

 although in the inner-dnnes, lies only 2200 M. from the Haarlem- 

 meer polder. Another well, some 100 M. north of the (yommon-Hall 

 at Heemstede, at about 1300 M. from that polder and still in the 

 inner dunes, had on May 29^'' , a level of 0.78 M. '.- A.P. In a thii-d 

 one, nearly 30 M. ! A.P. deep, situated within the precincts of the 

 community of Heemstede, but at only 440 M. from the Haarlemmer 

 polder, on Bosbeek, at the border of the imier dunes, and under 

 meteorologie conditions admittting of comparisoji, the level of the water 

 was 1.29 M.-i- A.P. A well on the l.eyden Canal, deep 32 M. ^ A.P., 

 near the remise of the Harlem Electric Tram, on April 9^^' 1903, 

 had a level of 0.225 M. -f A.P. This well, within the Veenpolder 

 (Summer-Level -^ 0.75 M.), lies one side at 3700 M. from the encircling 

 canal of the Haarlemmermeer polder, but also at only 1400 M. tVom 

 the Noordschalkwijk polder, (Snmmer-Level-r 1.25 M.) and the other 

 side about 1 K.M. from the dunes. A well near the Harlem Gas 

 Works, in the Veenpoldei' (; 1.40M. Summer-Level), 1700M. from 

 the encircling canal of the H.M.P., had, on March 31^^ 1903, a level 

 of abont 1.00 M. ^ A.P., and in a well on the gronnds, resei'ved 

 for the Harlem Abattoii', the level on April 4^'' was 'J .08 M. f A.P. 

 This well lies in the Roomolen polder (Summer-Level ^ 1.25 M.), at 

 1300 M. from the encircling canal of the H. M. P. 



On the other hand in a \vell at Hillegom (behind the building of 

 the Hillegom Bankvereeniging), sunk down (o 39 M. ^.- A. P., 

 1200 from (he Haarlemmermeer jiolder, the level of (he wa(er on 

 Ai)ril 8^"' 1903 was only 1.20 M. ^ A.P. Although equally far from 

 that polder as the \^'ell near the Common-Hall at Heemstede, the 

 distance that separates this w^ell at Hillegom from the central range 

 of dimes, l)eing 2900 M.; that at Heemstede only 1650 M. The 

 n))|)er-soil moreover at Hillegom is much richer in clay than that 

 at Heemstede, the dee[) nnderground water consequently on the first 



