Cooley's Cyclopaedia of Practical Receipts Volume Ii Part 205

=SEN'NA.= _Syn._ SENNA, SENNae FOLIA, L. There are three princ.i.p.al varieties:--

1. ALEXANDRIAN SENNA (SENNA ALEXANDRINA--B. P., Ph. L., E., & D.), referred in the, Ph. L. to _Ca.s.sia officinalis_ and _Ca.s.sia obovata_, in the Ph. D. to _Ca.s.sia acutifolia_ (Delile), and in the Ph. E. to various species of ca.s.sia. The leaves are "unequal at the base, ovate acute, or obovate mucronate." (Ph. L.) It is generally mixed with the leaves of _Solenostemma Argel_ (argel leaves), the presence of which is often the occasion of much griping. The leaf of argel is fully an inch long, warty, regular in its formation, and the lateral nerves are imperfectly seen on the under side; whilst that of the true Alexandrian senna never exceeds 3/4 inch in length, is oblique, and the nerves on the under side are very conspicuous.

2. INDIAN SENNA (SENNA INDICA--B. P.; Ph. L., & E.) is referred to _Ca.s.sia officinalis_ in the Ph. L., and in the Ph. E. & D. to _Ca.s.sia elongata_ (Lemaire, Lisancourt). The leaf is "unequal at the base," and "Lanceolate." (Ph. L.)

3. TINNEVELLY SENNA, forming the finest Indian, now introduced into the Ph. D., is therein described as composed of the leaflets of _Ca.s.sia oblongata_. These are pale green, thin, flexible, and from 1 to 2 inches long, and nearly 1/2 inch broad. This variety is equal in medicinal virtue to the best Alexandrian, and is to be preferred, on account of its being imported perfectly free from adulteration.

Senna is purgative in doses of 10 to 30 gr., either in powder or made into an infusion of tea with Water, combined with ginger, caraways, or some other aromatic, to prevent griping. It acts chiefly on the small intestines, and generally effects its purpose within 4 hours after being taken.

=SE"PIA.= A pigment prepared from the 'ink' or black fluid secreted by _Sepia officinalis_ (Linn.), and several other varieties of cuttle-fish.

The contents of the 'ink bags' are insp.i.s.sated as soon as possible after collection, and then form the crude sepia of commerce. This is prepared for artists by boiling it for a short time in a weak lye of caustic alkali, precipitating the solution with an acid, and well washing and carefully drying the precipitate by a gentle heat. It possesses a fine brown colour, and is used like Indian ink.

=SER'PENTARY.= _Syn._ VIRGINIAN SNAKE-ROOT; SERPENTARIA RADIX (B. P.), SERPENTARIae RADIX, SERPENTARIA (Ph. L. & E.), ARISTOLOCHIA SERPENTARIA (Ph. D.), L. An excellent stimulating diaph.o.r.etic and tonic; in typhoid and putrid fevers, dyspepsia, &c. It is admirably suited to check vomiting and to tranquilise the stomach, particularly in bilious cases. (Dr Chapman.)--_Dose_, 10 to 20 gr., every third or fourth hour, its use being preceded by an aperient.

=SE"RUM.= _Syn._ SERALb.u.mEN. The clear pale fluid in which the blood-globules float, and which separates from blood during its coagulation. It is, essentially, a feebly alkaline solution of alb.u.men.

See ALb.u.mEN.

=SESQUI-.= See NOMENCLATURE.

=SE'TON.= _Syn._ SETACEUM. An artificial ulcer, made by pa.s.sing a portion of silk or thread under the skin by means of a seton needle, a part of which is drawn through daily, and thus keeps up a constant irritation.

Occasionally the thread is anointed with some irritating substance for the purpose of increasing the discharge.

=SEVEN SEALS, or Golden Wonder--Dr Radcliffe's Great Remedy.= According to the prospectus, this remedy is good for cholera morbus, dysentery, diarrha, burns, sprains, rheumatism, warts and corns, and all diseases.

In a quadrangular bottle we find about 95 grammes of a brownish-orange clear fluid, which is a spirituous tincture of cayenne pepper mixed with ether, chloroform, American oil of peppermint, and a little camphor. The proportion of these ingredients is, approximately, 4 grammes ether, 6 grammes chloroform, 4 gramme camphor or camphoraceous oil, 2 grammes oil of peppermint, 35 grammes tincture of capsic.u.m. 50 grammes spirit of wine (90 per cent.) (Hager.)

=SE'VUM (Prepared).= _Syn._ SEVUM PRaePARATUM (B. P.), SEVUM MAGNETIc.u.m, L.

_Prep._ 1. ('Pharm. Journ.') Mould candles, at least 2 years old, melted by a very gentle heat, and strained from the wicks.

2. As MAGNETIC ADEPS. Used to make mercurial ointment. Triturated with 8, 12, or 16 times its weight of quicksilver, the globules are completely extinguished in from 10 to 15 minutes.

=SEWAGE, Removal and Disposal of.= The waste and putrescible refuse discharged from dwelling-houses by house-pipes and drains into sewers may be said, in general terms, to consist, besides human faeces and urine,[150]

of the dirty water and soapsuds arising from washing our bodies, our houses, and linen, more or less foul, as well as the water which, having been used for cooking operations, necessarily contains variable quant.i.ties of mineral and vegetable matter.

[Footnote 150: In the drainage of some towns the faeces are not allowed to enter the sewers. This, however, is the exception.]

The above statement will have prepared us not only for the complex nature of sewage water as shown in the following tables, but also for the variability in the amount of its const.i.tuents, this latter condition depending upon locality, and, as experiment shows, the hour of the day at which the sewage was collected.

_Composition of Sewer Water_ (WAY).

+-------------------------------+----------------------------------+ Grains per Gallon. +--------+-------+-------+---------+ 1. 2. 3. 4. +-------------------------------+--------+-------+-------+---------+ Organic matters (soluble) 1940 4103 1230 } 920 Organic matters (suspended) 3910 1700 2437 } Lime 1013 1471 1252 1125 Magnesia 142 182 159 135 Soda 401 240 241 189 Potash 366 357 331 109 Chloride of Sodium 2640 2261 3430 558 Sulphuric Acid 534 531 640 343 Phosphoric Acid 263 576 248 064 Carbonic Acid 901 892 1176 } Silicia {Oxide of Iron} 620 1355 646 } 477 {Oxide of Zinc} Ammonia 748 843 788 +--------+-------+-------+---------+ 13478 14511 12578 3920 +-------------------------------+--------+-------+-------+---------+

_London Sewer Water_ (LETHEBY).

+-----------------+---------------------------------------------+ Grains per gallon. +--------------+--------------+---------------+ Day Sewage. Night Sewage. Storm Sewage. +-----------------+--------------+--------------+---------------+ Soluble matters 5574 6509 7026 Organic matters 1508 742 1475 Nitrogen 544 519 726 Mineral matters 4066 5767 5571 Phosphoric acid 085 069 103 Potash 121 115 161 Suspended matters 3815 1399 3188 Organic 1611 748 1755 Nitrogen 078 029 067 Mineral 2204 651 1433 Phosphoric acid 089 064 098 Potash 808 004 016 +-----------------+--------------+--------------+---------------+

Letheby states that the sewer water in towns with water-closets has the following average composition per gallon:

Organic matter 2772 Nitrogen 621 Phosphoric acid 157 Potash 203

Sewer water placed under the microscope reveals various dead decaying matters, besides swarms of bacteria, ciliated infusoria, ambiform bodies, and fungi, consisting of spores and mycelium. The rotifera, diatoms, and desmids are few in number.[151] That a fluid having a composition such as sewage water has been shown to possess, when mixed with solid excreta, would, from the decomposition that so soon takes place in it, seriously endanger the health of those in whose habitations it was allowed to remain, is so self-evident to the sanitarian and pathologist that it is no wonder every civilised community should endeavour to get rid of this refuse from their habitations as speedily and effectively as possible. But the removal of the home sewage is a proceeding as illogical as it is imperfect if we afterwards neglect so to dispose of it as to render it innocuous or devoid of danger to the public health. The old method of getting rid of sewage (even when deprived of the faecal matter) by turning it into rivers and streams, has, more particularly since the Report of the Rivers Pollution Commissioners in 1870, been gradually abandoned. That when sewer water pa.s.ses into a river it undergoes a great amount of purification from oxidation, subsidence, and the agency of water-plants is undeniable.

[Footnote 151: Parkes.]

Letheby considered that if sewage mixed with twenty times its bulk of water flowed for nine miles it would be perfectly oxidised. It appears, however, from the experiments of Frankland, that so far as sewage when mixed with twenty times its volume of water being oxidised during a flow of ten or twelve miles, scarcely two thirds of it would be so destroyed in the flow of 168 miles, at the rate of one mile per hour, or after the lapse of a week. The results of Frankland's experiments led him to infer that there is no river in the United Kingdom of sufficient length to effect the destruction of sewage by oxidation; and he adds, "there is no process practicable on a large scale by which the noxious material (sewage matter) can be removed from water once so contaminated, and, therefore, I am of opinion that water which has been once contaminated by sewage or manure matter is thenceforth unsuitable for domestic use."

The discharge of sewage water, whether with or without solid excreta, into our springs and rivers, was a practice so dangerous and prejudicial to health that it is no cause for wonder the Legislature should, during the session of 1876, have pa.s.sed a measure the object of which was after the lapse of one year to facilitate legal proceedings being inst.i.tuted against persons who permitted sewage or other deleterious refuse to flow into rivers or streams. This measure, known as the "Rivers Pollution Prevention Act," is now in force, and permits offenders to be proceeded against; but it still leaves unsolved the important hygienic problem--How are we ultimately and with safety to the community to dispose of our sewage?

The numerous processes (the chief of which will be brought under notice) proposed for the attainment of this end have been divided by writers and authorities on sanitary science into--

1. WET METHODS.

2. DRY METHODS.

1. WET METHODS. These comprise the removal of excreta--(1) By discharging it into running water. (2) By storage in tank with overflow. (3) By carrying it into the sea. (4) By precipitation. (5) By irrigation and filtration.

(1) _By discharging it into running water._ Our previous remarks have already shown in what respect this proposal is fallacious, and why it has, therefore, been discontinued.

(2) _By storage in tank with overflow._ In this process the sewage runs into a well-cemented tank fitted with an overflow pipe, which sometimes leads into a second tank arranged in the same manner; the solids subside, and are removed from time to time, whilst the liquid is allowed to run away. Instead of permitting the liquid to escape into a ditch or stream, it has been proposed to carry it into drain pipes, which are buried from half a foot to a foot in the subsoil, where it will be readily sucked up by the roots of gra.s.ses. This plan is only suited for small villages, or for a single house or mansion.

(3) _By carrying it into the sea._ The precautions to be observed in the working of this system are, wherever possible, to let the outlet or discharge pipe, which conveys the sewage to the sea, be always under water even at ebb tide, and to take special care that the wind does not blow up the sewers. A tide-flap, opening outwards, which is usually fixed by a hinge on the sewer at its outlet, will obviate this last contingency. At high water the tide will fill the outfall sewers to its own level, and to that extent will check the discharge of sewage, and thus cause a deposit in the sewers filled with mixed sea water and sewage. It is most important that this should be removed.

"If the sewage cannot be got well out to sea, and if it issues in narrow channels, it may cause a nuisance, and may require to be purified before discharge."[152]

[Footnote 152: Parkes.]

(4) _By precipitation._ The simplest of the plans proposed for this method of removal is by subsidence only, and would afterwards permit the discharge of the supernatant sewage water into running water or over the land. The removal of the solid material is effected in a manner somewhat similar to that followed in plan No. 2, but as the thin water which runs off must, when poured into rivers or streams, be almost as dangerous as the sewage itself, the process of precipitation by settlement alone has little to commend it over the old rude and objectionable practice, a circ.u.mstance that in these days will doubtless lead to its entire prohibition.

In order to ensure greater purification the sewage in the subsiding tanks is now usually mixed with certain chemical reagents, which, it is believed, have the effect not only of speedily precipitating the solid materials, but also carrying down injurious matters suspended in the sewage water, thus rendering it sufficiently pure to be discharged without risk to health into any watercourse.

Of the numerous precipitants employed for this purpose, we may mention the following:

_Lime and salts of lime._ Quicklime, in the proportion of 8 gr. to a gallon of water; or 1 lb. to about 600 galls. of sewage; lime, with the addition of about a fortieth of its weight of chloride of lime; calcic phosphate dissolved in sulphuric acid; Whitehead's patent, which consists of a mixture of mono- and dicalcic phosphate; chloride of calcium.

_Aluminous compounds._ Bird's process--A mixture of aluminous earths and sulphuric acid. Andersons and Lenk's--Impure sulphate of alum; refuse of alum works, either alone or mixed with lime or charcoal. Scott's cement process--Clay mixed with lime; natural phosphate of aluminium dissolved by sulphuric acid and mixed with lime.

The quant.i.ties of the above substances when used as precipitants vary, in some of them fifty, and in others eighty grains to a gallon of sewer water being employed.

_Magnesium salts._ Impure chloride of magnesium mixed with superphosphate of lime.

_Carbon._ As vegetable charcoal, peat, seaweed charcoal, carbonised tan, lignite, and Boghead c.o.ke.

_Iron._ In the form of sulphate. Ellerman's and Dale's--Perchloride; the sulphate is sometimes mixed with coal dust.

_Manganese._ Condy's fluid.

_Zinc._ As sulphate and chloride.

_Sillar's process._ The A. B. C. process, so called because composed of alum, blood, charcoal, and clay.