CHAPTER XIII. ABSORPTION.

 The advantage of knowing the relative absorptive capacity of bricks has been stated in these pages in divers¹ connexions. The means of arriving at the total capacity for absorption of water, as generally practised by experimenters, are very incomplete and founded on an erroneous principle. It is admitted by all that absorption is one of the very best tests as to the quality of a brick, but such tests are meaningless unless they imitate one or other or several of the influences to which the brick would be subjected on being used in the building, or other structure.

A common method is to weigh the brick when dry and then to immerse it in water for periods varying from one to three days, subsequently re-weighing it, the difference in weight between the dry and wet states being termed the brick’s “absorptive capacity.”

Mr. Heinrich Ries remarks16 that the absorption is determined² by weighing the thoroughly³ dry samples, immersing in clean water from 48 to 72 hours, then wiping dry and weighing again. Vitrified bricks should not show a gain in weight of over 2 per cent. There are cases where bricks of apparently⁴ good quality shew a greater absorption than this, but they have great toughness and refractory⁵ qualities. Bricks made from fire-clays which will not vitrify so easily will, naturally, show higher absorption.

133 Again, Mr. E. S. Fickes, of Steubenville, Ohio, has recently made17 a large series of valuable tests of both paving and building bricks, in which he shews the connexion between the power of absorption and the strength of the materials experimented with. Mr. Fickes’ more important conclusions are:—

1. The strength of the building brick, both transverse and crushing, varies in tolerably close inverse⁶ ratio with the quantity of water absorbed in twenty-four hours. The strongest bricks absorb the least water.

2. Good building bricks absorb from 6 to 12 per cent. in 24 hours, and with no greater absorption than 12 per cent. will ordinarily show from 7,000 to 10,000 or more pounds per square inch of ultimate crushing strength.

3. Poor building bricks will absorb one-seventh to one-fourth of their weight of water in 24 hours, and average a little more than one-half the transverse and crushing strength of good bricks.

4. An immersed brick is nearly saturated⁷ in the first hour of immersion⁸, and in the remaining 23 hours the absorption is only five-tenths to eight-tenths of 1 per cent. of its weight, as a rule.

These experiments are of much interest and are probably approximately correct; but we venture to think that if the absorption experiments had been carried out in a different manner, the results would have been still more valuable.

Long before the publication of the results of the last mentioned series of experiments, the present writer had discovered the close connexion which subsists⁹ between the relative absorptive capacity of bricks and their strength; a slight correction must be applied¹⁰ for134 specific gravity. We are not prepared to enter into this subject at any length, but it may be observed that we should not have arrived at such close results had we experimented in the same way as the American authors just quoted (or others, for the matter of that).

When you completely immerse a brick in water you prevent the escape of air to a very large extent from the pores in the interior of the brick. An old-fashioned way of overcoming this difficulty, was to place the brick in the receiver of an air-pump and exhaust the air, subsequently immersing the brick. This latter method certainly possessed¹¹ the merit of enabling the experimenter to arrive at total absorption very rapidly, but it did not imitate natural processes any more than does the thorough immersion of the brick in water.

A writer in the Builder of May 25th, 1895, p. 397, experimented as follows:—The bricks were placed in water in a large vessel¹², on edge, supported where necessary by flat blocks, to bring the uppermost face of each brick about ?-inch above the surface of the water. Experience had shewn that by completely immersing a brick, the air did not get an opportunity of escaping from its pores with the same facility as when one surface was left out of water. This disability, it was found, materially impaired¹³ the results of the rate of absorption (rate, as well as total tests, being carried out). By arranging the experiments in the manner described, there can be no doubt that each brick absorbed the maximum quantity of water possible; at any rate, there was no water-pressure from above to retard¹⁴ the expulsion of the air.

The tests in the last-mentioned case extended over one week, the relative absorption being taken at intervals¹⁵ of 1 second, 1 minute, 30 minutes, 1 day, and at the end of the week. It was found that English vitrified bricks135 absorbed from 1.16 to about 1.85 per cent. in one week; white glazed¹⁶ and good red and blue facing bricks from 5.31 to 10.34 per cent. in one week; wire cut facers and rubbers, with white gaults, imbibed¹⁷ as much as from 12.93 to 20.50 per cent. of their dry weight in one week. The rate of percolation¹⁸ suggested many interesting problems, not the least important being the effect of chemical decomposition¹⁹ in prolonged immersions, whereby after being quiescent²⁰ for a few days (after taking in the water for a few hours), absorption “burst out” again and continued to the end of the week. One thing is very apparent from this, namely, that for the lower grade brick even an immersion for one week is not sufficient for practical purposes. The writer remarks, “some of the red bricks from Bracknell, being placed in the vicinity of the white gault bricks (in the water), discoloured the latter to such an extent as to disfigure them. It was not merely a surface colouration; it extended to at least ?-in. into the interior. The red colouring matter was iron, but there was not enough of it by weight dissolved to materially interfere²¹ with the experiments. This very clearly shews, however, the folly²² of erecting²³ a building coursed with white and red bricks, when both are very absorbent and the red has so little hold of the iron of which it is partly composed—unsightly stains are bound to appear.”

This question of the solubility²⁴ of certain ingredients of bricks, has not received the attention it deserves; and closely connected with that is gradual decomposition, whereby the brick becomes more and more porous—a potent²⁵ factor in its ultimate destruction.

1 divers   

adj.不同的；种种的

参考例句：

• He chose divers of them,who were asked to accompany him.他选择他们当中的几个人，要他们和他作伴。
• Two divers work together while a standby diver remains on the surface.两名潜水员协同工作，同时有一名候补潜水员留在水面上。

2 determined   

adj.坚定的；有决心的

参考例句：

• I have determined on going to Tibet after graduation.我已决定毕业后去西藏。
• He determined to view the rooms behind the office.他决定查看一下办公室后面的房间。

3 thoroughly   

adv.完全地，彻底地，十足地

参考例句：

• The soil must be thoroughly turned over before planting.一定要先把土地深翻一遍再下种。
• The soldiers have been thoroughly instructed in the care of their weapons.士兵们都系统地接受过保护武器的训练。

4 apparently   

adv.显然地；表面上，似乎

参考例句：

• An apparently blind alley leads suddenly into an open space.山穷水尽，豁然开朗。
• He was apparently much surprised at the news.他对那个消息显然感到十分惊异。

5 refractory   

adj.倔强的，难驾驭的

参考例句：

• He is a very refractory child.他是一个很倔强的孩子。
• Silicate minerals are characteristically refractory and difficult to break down.硅酸盐矿物的特点是耐熔和难以分离。

6 inverse   

adj.相反的，倒转的，反转的；n.相反之物；v.倒转

参考例句：

• Evil is the inverse of good.恶是善的反面。
• When the direct approach failed he tried the inverse.当直接方法失败时，他尝试相反的做法。

7 saturated   

a.饱和的，充满的

参考例句：

• The continuous rain had saturated the soil. 连绵不断的雨把土地淋了个透。
• a saturated solution of sodium chloride 氯化钠饱和溶液

8 immersion   

n.沉浸；专心

参考例句：

• The dirt on the bottom of the bath didn't encourage total immersion.浴缸底有污垢，不宜全身浸泡于其中。
• The wood had become swollen from prolonged immersion.因长时间浸泡，木头发胀了。

9 subsists   

v.（靠很少的钱或食物）维持生活，生存下去( subsist的第三人称单数 )

参考例句：

• This plant subsists in water holes only during the rainy season. 这种植物只有雨季在水坑里出现。 来自辞典例句
• The hinge is that the enterprise subsists on suiting the development of data communication. 适应数据通信的发展是通信企业生存的关键。 来自互联网

10 applied   

adj.应用的；v.应用，适用

参考例句：

• She plans to take a course in applied linguistics.她打算学习应用语言学课程。
• This cream is best applied to the face at night.这种乳霜最好晚上擦脸用。

11 possessed   

adj.疯狂的；拥有的，占有的

参考例句：

• He flew out of the room like a man possessed.他像着了魔似地猛然冲出房门。
• He behaved like someone possessed.他行为举止像是魔怔了。

12 vessel   

n.船舶；容器，器皿；管，导管，血管

参考例句：

• The vessel is fully loaded with cargo for Shanghai.这艘船满载货物驶往上海。
• You should put the water into a vessel.你应该把水装入容器中。

13 impaired   

adj.受损的；出毛病的；有（身体或智力）缺陷的v.损害，削弱( impair的过去式和过去分词 )

参考例句：

• Much reading has impaired his vision. 大量读书损害了他的视力。 来自《现代汉英综合大词典》
• His hearing is somewhat impaired. 他的听觉已受到一定程度的损害。 来自《现代汉英综合大词典》

14 retard   

n.阻止，延迟；vt.妨碍，延迟，使减速

参考例句：

• Lack of sunlight will retard the growth of most plants.缺乏阳光会妨碍大多数植物的生长。
• Continuing violence will retard negotiations over the country's future.持续不断的暴力活动会阻碍关系到国家未来的谈判的进行。

15 intervals   

n.[军事]间隔( interval的名词复数 )；间隔时间；[数学]区间；（戏剧、电影或音乐会的）幕间休息

参考例句：

• The forecast said there would be sunny intervals and showers. 预报间晴，有阵雨。
• Meetings take place at fortnightly intervals. 每两周开一次会。

16 glazed   

adj.光滑的，像玻璃的；上过釉的；呆滞无神的v.装玻璃( glaze的过去式)；上釉于，上光；（目光）变得呆滞无神

参考例句：

• eyes glazed with boredom 厌倦无神的眼睛
• His eyes glazed over at the sight of her. 看到她时，他的目光就变得呆滞。 来自《简明英汉词典》

17 imbibed   

v.吸收( imbibe的过去式和过去分词 )；喝；吸取；吸气

参考例句：

• They imbibed the local cider before walking home to dinner. 他们在走回家吃饭之前喝了本地的苹果酒。 来自《简明英汉词典》
• Hester Prynne imbibed this spirit. 海丝特 - 白兰汲取了这一精神。 来自英汉文学 - 红字

18 percolation   

n.过滤，浸透；渗滤；渗漏

参考例句：

• This corresponds to the percolation phase of the drying mechanism. 这相当于干化机理的渗滤阶段。 来自辞典例句
• The percolation clusters with various occupying probability are constructed. 构造了具有不同占据概率的逾渗集团。 来自互联网

19 decomposition   

n. 分解, 腐烂, 崩溃

参考例句：

• It is said that the magnetite was formed by a chemical process called thermal decomposition. 据说这枚陨星是在热分解的化学过程中形成的。
• The dehydration process leads to fairly extensive decomposition of the product. 脱水过程会导致产物相当程度的分解。

20 quiescent   

adj.静止的，不活动的，寂静的

参考例句：

• It is unlikely that such an extremist organization will remain quiescent for long.这种过激的组织是不太可能长期沉默的。
• Great distance in either time or space has wonderful power to lull and render quiescent the human mind.时间和空间上的远距离有一种奇妙的力量，可以使人的心灵平静。

21 interfere   

v.(in)干涉，干预；(with)妨碍，打扰

参考例句：

• If we interfere, it may do more harm than good.如果我们干预的话，可能弊多利少。
• When others interfere in the affair,it always makes troubles. 别人一卷入这一事件，棘手的事情就来了。

22 folly   

n.愚笨，愚蠢，蠢事，蠢行，傻话

参考例句：

• Learn wisdom by the folly of others.从别人的愚蠢行动中学到智慧。
• Events proved the folly of such calculations.事情的进展证明了这种估计是愚蠢的。

23 erecting   

v.使直立，竖起( erect的现在分词 )；建立

参考例句：

• Nations can restrict their foreign trade by erecting barriers to exports as well as imports. 象设置进口壁垒那样，各国可以通过设置出口壁垒来限制对外贸易。 来自辞典例句
• Could you tell me the specific lift-slab procedure for erecting buildings? 能否告之用升板法安装楼房的具体程序？ 来自互联网

24 solubility   

n.溶解度；可解决性；溶度

参考例句：

• Elasticity, solubility, inflammability are paradigm cases of dispositions in natural objects. 伸缩性、可缩性、易燃性是天然物体倾向性的范例。 来自辞典例句
• Solubility products are sometimes known with similar accuracy. 溶度积时有时也具有同样的准确度。 来自辞典例句

25 potent   

adj.强有力的，有权势的；有效力的

参考例句：

• The medicine had a potent effect on your disease.这药物对你的病疗效很大。
• We must account of his potent influence.我们必须考虑他的强有力的影响。