Ch 39 Tides and Sea Walls

8/12/2019 Ch 39 Tides and Sea Walls

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From Corn to Cordite. Copyright John Williams 2010

Chapter Thirty Nine :

Tides and Sea walls.

Contents:

The Suggestion is That Tidal heights were greater in past times.

The evidene suggests that a hange in tidal heights has happened.

The arguments: !rom authorities and e"perts on greater tidal heights in the past

are as #ollows.

The $uth %rewery: %ier&rouweri'en (ran'e&oom )erenigde.

* tide ta&le #rom 1+,0.

-e#erenes.

The Sea walls at itsea

The /arly Sea walls proteting itsea all /state and the Sluie.

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Chapter Thirty Nine :

Tides and Sea walls.

t would &e interesting to disover what would the height o# the tides &een inpast times is there any evidene o# hange.

The Suggestion is That Tidal heights were greater in past times:

Should the reader want a short onise e"planation o# sea levels then this

is the re#erene #or you: ordon. $.3 4ean Sea 3evel around the %ritish sles.

5*6

$alton and 3aver 5%6 suggested that an e"amination o# tidal height in

Colhester showed that ranaries whih were not 700 years old were regularly

#looded in 1800. The #oundation level o# the -oman settlement in the area was at

the &ottom edge o# low water spring tides. * 9ui alulation shows that allthings &eing e9ual then this would &e e9uivalent to 1+ #eet &elow the ranaries.

The evidene suggests that a hange in tidal heights has happened:

This evidene &y $alton and 3aver suggests that sea level rises were

happening in the 1+thentury. 5%6 Jensen states that Sea levels in -oman times

were 1; #eet lower that today. 5C6.

Why would the sea level &e rising sine -oman times< We have to

onsider phenomena nown as =/ustay> and =sostay>. /ustay is the inreased

amount o# water held in the oeans &asins? i# it inreases then #looding is

possi&le in plaes. sostay is di##erent? this is when the rust or the land &ends?

tilts or de#orms. The e##et o# this &ending or tilting is seen in the Thames valley.

The theory goes lie this? during the last ie age huge masses o# ie rested on the

northern parts o# /ngland and Sotland this depressed the level o# the land and

tilted the oast in the south upwards. When the ie melted the weight was

removed and the land mass started to reover and rise so Sotland rose &ut the

Thames valley san. /videne e"ists to show that the Sottish &eahes have risen

2; #eet and lowering has ourred in the Thames area.586

The arguments: !rom authorities and e"perts on greater tidal heights in the past

are as #ollows:

Taser omments that a great deal o# em&aning was done &y the

-omans who were master &uilders? this is easily evidened at %aring and

$agenham. /lsewhere it was the $uth who were involved in em&aning the

Thames. 5$6

!air&ridge loos at hanges during the -oman period? the lower plot on

the sea level graph 5shown on age @116 shows that in %CA*$ the level drops

until *$ 1;0 then rises until *$ ;00 the drops again. 5/6? 5!6? 56? 56? 56? 5J6.

t would not &e unreasona&le to e"amine the #ortunes o# a loal port that

had &een ative sine the1;th and 1Bth

Century. The Town o# 3eigh would suitadmira&ly.

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3eigh was desri&ed in 1;B; as: A very proper towne, well furnished of

(Rubbed) mariners, where ships do ride, all maner cranes and other thinges.

Fourteen ships, 6!"# tons $ mariners% 516 and in 1B07 it is reorded that 8

vessels o# 200@00 Tons were &ased in 3eigh.526. The 3eigh &ased 7;0 ton ship

the =lo&e> was plying her trade to the /ast ndies while the vessel =3ittle John>

was visiting South *#ria.n 1;,+? 3eigh sent eight ships and two innaes 5small support vessels6 to

support $raes !leet against the Spanish. Then in 1;,8 3eigh sent ships to

ortugal to support $rae as =ired 4erhantmen> #or whih they reeived

2 shillings per ton per month. 576.

n 1B18 3eigh had 21 vessels. arwih and Colhester having 7B and 20

respetively. )ange? %en#leet and !o&&ing having only one. 5@6.

n 1B2, it is reorded that the County only had 708 sailors and 7;+

!ishermen? with 7@ ships at 100 tons and 1B ships at 8; tons.

We must ompare this with #igures #or 1;+2 when 3eigh alone had 71

vessels with 270 mariners and #ishermen. 5;6.

*n interesting #at is that there was a small port alled 4ilton o# 4iltonamlet? it was reorded that in the early 1B00>s it had si" vessels &etween 120

and 700 tons and served the /ast ndies. t no longer e"ists? Nihols reords that

4orant in 1+B, states that the remains o# a hapel an &e seen at the low water

mar. The loation seems to &e somewhere on the Southend Sea#ront. 5226.

Something was happening? orts lie 3eigh would &e very susepti&le to

what is alled &y Sea#arers =Constrained &y $raught>? this simply means that

there needs to &e enough water to allow the ship to enter the do or ome

alongside to &e unloaded? larger ships would go elsewhere. t is not impossi&le

and worth onsidering? that the 4ediaeval su&mergene had some in#luene on

this onstraint.

t is important to point out that #rom 1+;01,@0 huge amounts o# orn

went to $uth &reweries the repeal o# orn laws in the early 1,00>s aused it go

the other way when the importation o# orn inreased? possi&ly on #oreign ships.

5B6? 5+6? 586? 5106.

%ier&rouweri'en (ran'e&oom )erenigde.

* )ery old $uth &rewery esta&lished in 1B+1? now losed. To 9uote #rom

the $uth Tourist %oard. ollandDs hop gardens #irst appeared in the 1@th

entury and &reweries &lossomed during the 4iddle *ges? although the

housewives did not stop &rewing their own &eer. /very $uth ity had a

&rewery? and aarlem? $el#t? ouda? and *mers#oort produed enough &eer #or

e"port to !landers. *msterdam &eame the ma'or &rewing enter in the 1;th

entury. %y the 1+th entury there were +00 &reweries in olland and aninrease in demand #or &eer as it was used #or &oth drining and ooing

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raph o# Tidal variation over time. 5,6

/videne and arguments to e"plain how silting has ourred altering the usage o#

any tidal draught:

t an &e argued that the slight lowering o# the availa&le draught and the

ontinuing pro&lems aused &y 3ondon %ridge impeding o# the Thames #low andwas ausing siltation. Today? 3eigh is somewhat silted up and would have

di##iulty in handling the num&er and siEe o# vessels as #ormerly even i# the

inreased tidal height is allowed #or.

t is lear that an e"amination o# the Thames tidal region is that

enormous 9uantities o# silt streth #or miles. What aounts #or this apparent

hange

Ch 39 Tides and Sea Walls

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