that the failure of blood is first felt. The nervous centres, protected from the effects of sudden pressure by their envelopment of bony structure, feel the shock of the exhaustion secondarily. Thus the muscle suffering a reduced resistance of blood to the nervous stimulus, contracts as if it had received an excess of stimulus, and the phenomenon of primary convulsion is developed; in hæmorrhage this convulsion immediately precedes deliquium or syncope. In brief time, the nervous centres themselves becoming exhausted, the convulsions cease, and none but the muscular movements of the organic life, respiration and circulation, remain. These while they last feed still in a passive state the nervous centres and muscular centres; and if the cause of exhaustion at this stage be stopped and the body be resupplied with means of life, recovery takes place without the necessary return of convulsive action; but if the exhaustion proceed, then follows the secondary phase, the failure of the organic system, and with that a repetition of the phenomenon of primary failure, viz. a second general convulsion, terminating in death.

The convulsion of hæmorrhage is, I repeat, the typical form of the conditions I have portrayed; but in death from chloroform and similar narcoties, the phenomena are sometimes equally striking. The convulsion and rigidity which mark the second degree of narcotism indicate the first break of balance between the nervous and the muscular centres; the period of the third and fourth degrees of narcotism, during which there is complete paralysis of voluntary and of conscious power, marks the interval when all life is suspended on the organic or vegetative nervous system; the final convulsion that precedes death marks and proclaims the moment when the organic force itself breaks down, leaving the whole organism motionless and, as we say, dead.

ON CONDENSATION OF WATER ON THE BRONCHIAL SURFACE DURING NARCOTISM.

It has occurred to me often to observe that the physiological action of narcotic vapours during inhalation is greatly modified by the condition of the atmospheric air in respect to its dryness and its moisture. When the atmosphere is extremely dry, the action of a narcotic vapour is greatly increased, and recovery from its effects is remarkably easy; on the contrary, when the air is saturated with water vapour the action is impeded; and if the air be at the same time cold and moist, the process of narcotism is often greatly impeded, while recovery after it has been established is prolonged in proportion. But the fact I wish particularly to bring forward is, that when the body of an animal becomes profoundly narcotized, and the insensibility is long maintained, during conditions in which the air is cold and moist, there occurs not unfrequently an actual condensation of water in the minute bronchial passages, which condensation leads to as low asphyxia, and, if it be continued, to actual death. This accident is best seen in cases of narcotic poisoning from hydrate of chloral; it may also be observed after poisoning from opium and other narcotics, as well as after long exposure to extreme cold.

There are two causes at work to produce the condensation: the one is the obstacle to evaporation of watery matter from the surface of the animal membrane into the air; the other the deficiency of force, in an animal whose general temperature is reduced, to raise the vapour of water from the blood, and to expel it from the pulmonary organs in the state of vapour.

Whenever in any case condensation of water, from the causes named, is set up, the danger continues in an increasing ratio; for the condensation tends to shut off the air from contact with the blood, the temperature of the

body (dependent always on the perfection of the respiratory process) decreases, and at last the respiratory change is prohibited altogether.

It is important in the extremest degree to remember the fact thus named in the treatment of cases of poisoning during which the animal heat is reduced. It will often turn the scale, in such instances, in favour of return to life, simply to place the body in a warm and dry air.

The fact is also of great interest, in a practical and physiological point of view, in relation to the phenomena of some exhaustive diseases. The cold sweats that are seen on the surface of the body in syncope, in the later stages of phthisis pulmonalis, and on the approach of death in many diseases, as also the chest-rattles, are due to the cause I have named above-condensation. They are evidences that the body has not sufficient power or force to produco a rapid natural evaporation of water from the exhaling surfaces.

Report of the Committee appointed to get cut and prepared Sections of Mountain-Limestone Corals for the purpose of showing their structure by means of Photography. The Committee consists of JAMES THOMSON, F.G.S., and Professor HARKNESS, F.R.S.

In our Report of last year we gave in detail the probable additions to our present list of fossil corals from the Mountain Limestone.

During the past year we have had several hundred specimens cut. Although many of these have been more or less spoiled, and their internal structure crushed and broken to such an extent that their specific characters cannot with any degree of certainty be made out, yet many of them reveal important structural characters which will enable us to add both genera and species to those before indicated. Many of the specimens cut have wellpreserved calices, which will enable us to figure and describe both their internal structure and external aspect, with a degree of certainty hitherto

unknown.

Although much progress has been made, we are convinced that many other facts will be revealed by further investigation; and we hope the Committee will be reappointed in order that we may continue this important inquiry.

We have not added any additional photographic plates to those exhibited last year at Liverpool. We were desirous of getting as large a number of specimens cut as the sum at our disposal would permit, in order that we might select the most characteristic generic forms for further plates.

At Liverpool we indicated that we were in the hopes of reproducing the most delicate structures by another process, which would be more serviceable for the purpose of publication. In this we are glad to state that we have been successful. By a simple process we are enabled to transfer the details of both genera and species to copper plates, from which any number of copies can be reproduced, of which we will avail ourselves when we are ready to publish in extenso. (Two plates so prepared were exhibited.)

We have placed in the British Museum and the Hunterian Museum of Glasgow duplicates of a number of the cut specimens which have already been described; other duplicates will be sent when they have been described and named.

Second Report of the Committee appointed to consider and report on the various Plans proposed for Legislating on the subject of SteamBoiler Explosions, with a view to their Prevention,—the Committee consisting of Sir WILLIAM FAIRBAIRN, Bart., C.E., LL.D., F.R.S., JOHN PENN, C.E., F.R.S., FREDERICK J. BRAMWELL, C.E., HUGH MASON, SAMUEL RIGBY, THOMAS SCHOFIELD, CHARLES F. BEYER, C.E., THOMAS WEBSTER, Q.C., and LAVINGTON E. FLETCHER, C.E. SINCE the first Report on the subject of "Steam-Boiler Legislation" was presented to the Meeting of the British Association, held last year at Liverpool, the Parliamentary Committee "appointed to inquire into the cause of SteamBoiler Explosions and the best means of preventing them" have presented their Report.

The consideration of the result of the Parliamentary Committee's inquiry clearly becomes one of the most important duties in reporting to the British Association on "the various plans proposed for legislating on Steam-Boiler Explosions, with a view to their Prevention." Unfortunately, however, the Parliamentary Report has been so recently published that there has not been time for its due consideration, or for the Committee appointed to treat on this subject to meet and confer thereon. Under these circumstances it has

been thought best not to attempt to enter upon the subject on the present occasion, but to postpone doing so until next year, after having an opportunity of watching the development of the measure, and its working when carried into actual practice; and therefore, in order that they might be in a position to report thereon to the next Meeting of the British Association, the Committee would beg to suggest their reappointment.

Report of the Committee on the " Treatment and Utilization of Sewage." Consisting of RICHARD B. GRANTHAM, C.E., F.G.S. (Chairman), Professor D. T. ANSTED, F.R.S., Professor W. H. CORFIELD, M.A., M.B., J. BAILEY DENTON, C.E., F.G.S., Dr. W. H. GILBERT, F.R.S., JOHN THORNHILL HARRISON, C.E., THOMAS HAWKSLEY, C.E., F.G.S., W. HOPE, V.C., Lieut.-Col. LEACH, R.E., Dr. W. ODLING, F.R.S., Dr. A. VOELCKER, F.R.S., Professor A. W. WILLIAMSON, F.R.S., F.C.S., and Sir JOHN LUBBOCK, Bart., M.P., F.R.S. (Treasurer). THE Committee, upon its reappointment at Liverpool last September (1870), proceeded at once to consider the subjects which seemed to demand immediate attention in furtherance of the investigation which had been again. entrusted to it.

The first steps taken were to endeavour to procure information from the towns where works have been constructed for the application of sewage to land by irrigation, and from the places where the dry earth or Moule's system is in operation.

In order to commence the inquiry, a list of towns was prepared, to each of which a printed form of queries was sent; but only eight places have answered the circular on irrigation, and only one that relating to the dry-earth process. The answers from the towns have been tabulated, and the Table will be found at the end of this Report (Appendix A).

During the construction of the present tanks at Breton's Farm in the winter, very accurate observations could not at all times be made; but nevertheless, during the extreme frost, samples were taken of the sewage and of the effluent water. The temperature of both, and also the temperature of the

atmosphere, was observed. Similar observations were made at Croydon and Norwood (see Section I.).

The observations as to the quantity and quality of the sewage and effluent water have been continued at Breton's Farm, with slight interruptions, as stated above, from the Meeting of the British Association at Liverpool down to the present time. The results of the gaugings are recorded in the Tables which will be found in Section II. of this Report.

The Committee has visited several sewage-farms, and examined the various methods that are pursued at them with a view to determining the practical conditions upon which the success of sewage-farming depends. They have had samples of sewage and of effluent water collected, and have had analyses made of them, which latter, with the remarks of the Committee, will be found in Section III.

The phosphate process of Messrs. Forbes and Price has been also examined by a Member of the Committee, and a description of the process, with an analysis of the effluent water from this process, is given in Section IV.

Analyses of the soil which has passed once and twice through earth-closets have been furnished by another Member; and the manner in which this process is carried out at Lancaster, with the results attained there, is described in Section V.

An ox which had been fed for the previous 22 months entirely on sewagegrown produce was slaughtered on July 15th at Breton's Farm, and the carcass examined by Dr. Cobbold and Professors Marshall and Corfield, in the presence of several Members of the Committee, with a view to ascertain the presence or absence of Entozoa in any stage of their existence. The results of this examination, and Dr. Cobbold's report, will be found appended (Appendix B).

The attention of the Committee has been drawn to certain anomalies in the figures given in the list of rainfalls in the "Tabulation compiled from returns furnished by 200 towns selected for classification," at the end of last year's Report.

On referring to the original returns, it has been found that the figures given in the Table are correctly taken from them.

SECTION I.—A Comparison of Results obtained in the purification of Sewage at three Irrigation Farms during the severe frost of last winter.

1. Breton's Farm, near Romford.

The following analyses show the composition of average samples of sewage and effluent water collected on the farm on January 2nd; cach sample was made by collecting five portions at different times, and mixing them in proportion to the flow at the time.

The sewage, after passing through the tank and pump, contains more solid matters in solution but much less in suspension than the sewage as it comes from the town; the agitation causes some of the suspended matter to pass into solution; and it will be noticed that the amount of albuminoid ammonia in solution is nearly doubled, showing that a considerable amount of nitrogenous organic matter formerly in a state of suspension has been dissolved.

This sewage is very much stronger than the average summer sewage, which only contains from 2.5 to 4 parts of actual ammonia in 100,000; and so one would hardly expect it to be so satisfactorily purified (especially considering the extreme frost and the want of growth) as the sewage was during the summer.

Nevertheless the purification was very satisfactory indeed; for the effluent water only contained 0.143 of actual ammonia, instead of 5.628, while the albuminoid ammonia was reduced from 0.524 to 0.059.

From this we see that very little nitrogen passes away in the form of ammonia or of organic nitrogen, even in winter, when vegetation has least to do with the purification.

Some of it passes away, however, in the form of nitrates and nitrites; but the amount which is thus lost is very little greater in the winter than in the summer, being 1.208 part in winter and about 1.106 part in summer in 100,000 parts.

Thus it appears that, with an underdrained soil, the sewage being obliged to pass through several feet of soil before it escapes, (1) oxidation goes on in winter as well as in summer, and almost all nitrogen lost is lost in an oxidized and inoffensive form, and (2) this loss is very slightly greater in winter with a very strong sewage than in summer with a weaker one; so that sewaging in the winter would appear to entail no extra loss of manure.

2. Beddington Farm, Croydon.

Three samples of Croydon sewage, taken from Beddington Fields, 3rd January, 1871.

The analyses show that the sewage applied to this farm contained on January 3rd, 1871, just about the same quantity of ammonia as that applied to Breton's Farm on the day before.

The effluent water contained 0.744 part of ammonia, or between five and six times as much as that at Breton's Farm; the albuminoid ammonia was less in actual amount in the effluent water; but the reduction was from 0.188 to 0.045, or to one fourth of the original amount; while in the last case it was from 0.524 to 0.059, or to between one cighth and one ninth of the original amount contained in the sewage as pumped on to the land. The nitrates and nitrites in the effluent water were in insignificant amount, thus