lowing the sinuosities of the bright streak; then a dark band, parallel to, and following, every irregularity of the bright streak; and then nearly another eighth of an inch of ribbon-like light. In another picture a very thin beaded flash has a precisely similar beaded streak, rather fainter than itself, running parallel to it, at a distance of about a sixteenth of an inch on the paper.

It might be suggested that the second fainter image was formed by internal reflection from the back surface of the glass plate; but it should be noticed that sometimes very thin flashes, which are not particularly bright, are so duplicated.

A far more probable cause is the double image formed by the internal reflections of doublet photographic lenses. All doublets are essentially two meniscus lenses, mounted with their concave surfaces facing one another. The greater portion of a strong point of light, passing through both lenses, forms the usual image on the plate; but a smaller portion is reflected from the concave surface of the rear meniscus on to the concave surface of the front lens, and from thence back through the rear lens to the sensitive plate. The amount of displacement depends on the angle formed between the direction of the bright point and the optical axis of the lens.

M. C. Moussette of Paris showed some photographs of the sun in which this double reflection image was very conspicuous; and there is not the slightest doubt that some lightning-flashes are bright enough to give this secondary image. M. Moussette also showed the photograph of a flash in which the centre of the flash was whitest, with a darker edge on either side. This may have been produced either by double reflection from the lens, or by internal reflection from the back of the glass plate. Two bands of light the primary and secondary images slightly overlapping would form an extra bright band where the overlap took place.

In the majority of cases, the folds of the ribbon formation are most obvious when the course of the flash is square to the width of the folds, and they are but slightly pronounced when in a line with them. This would suggest the idea of a shaking of the camera in the direction of the folds of the ribbon; but, if this is so, the duration of a lightning-flash must be much longer than is usually supposed.

The committee hope to have the opportunity of making some experiments on the photography of sparks from a coil or electrical influence machine. In the mean time they defer expressing an opinion as to whether lightning ever really takes a ribbon-like form till further evidence is available, but would point out that both sources of error the duplication of the image either by reflection inside the lens, or by reflection from the back of the plate — would be avoided by the use of single lenses, and of paper instead of glass supported films. The committee also forbear for the present from publishing a reproduction of a ribbon-like flash, till they are satisfied that such a form of lightning really exists, and that the whole appearance is not due to photographic causes.

In one picture, sent by Mr. Shepherd, there are five ordinary white flashes, and one dark streak of precisely the same character as the bright streaks. M. Moussette has suggested that this may be the result of a very bright flash, so over-exposing the plate as to produce the well-known inversion of a negative by over-exposure, as when the ball of the sun appears black on the positive print, instead of white. This is no doubt a possible explanation; but the committee would like further examples of this same appearance of dark flashes before expressing an opinion on the mat

ter.

The committee call attention to the fact that there is not the slightest evidence in the photographs of lightning-flashes of that angular zigzag or forked form so commonly seen in pictures.

In connection with this, they would call attention to a remarkable paper, communicated to the British Association in 1856, by James Nasmyth, F.R.S. Mr. Nasmyth says that he has never seen forked lightning of the angular zigzag form, and asserts that the true natural form of a primitive flash of lightning appears to Mr. Nasmyth to be more correctly represented by an intensely crooked line, and on several occasions he has observed it to assume the forked or branched form, but never the zigzag dovetail."

The Council of the Royal Meteorological Society are desirous of obtaining more photographs of flashes of lightning, as they believe that a great deal of research on this subject can only be pursued

by means of the camera, and would esteem it a great favor if any one would give them any assistance in this matter, either by send ing them copies of any photographs of flashes of lightning that may have already been taken, or by endeavoring to procure them, or to interest others in so doing.

It may perhaps be well to mention that the photography of lightning does not present any particular difficulties. If a rapid plate and an ordinary rapid lens with full aperture, be left uncovered for a short time at night during a thunder-storm, flashes of lightning will, after development, be found in some cases to have impressed themselves upon the plate. The only difficulty is the uncertainty whether any particular flash will happen to have been in the field of view. A rapid single lens is much more suitable than a rapid doublet; and it is believed that films on paper would effectually prevent reflection from the back.

The focus should be that for a distant object; and, if possible. some point of landscape should be included to give the position of the horizon. If the latter is impossible, then the top of the picture should be distinctly marked. Any additional information as to the time, direction in which the camera was pointed, and the state of the weather, would be very desirable. The council hope, now that the thunder-storm season is approaching, many photographers, both amateur and professional, may be found willing to take up this interesting branch of their art. A. F. N. New York, July 2.

The Name of America.

WILL you permit us to correct some erroneous ideas in your note on our work? Your reviewer, referring to the origin of the name 'America,' says that our account derives it from a Peruvian tribe, although the name was in use long before Peru was discovered. This, no doubt, is an unintentional misrepresentation, as no such tribe ever existed, the name 'Peru' having been given by the Spaniards to the kingdom of the Aymaras of Aymaraca, whose subjects, according to some authors, were also the chief race in the West Indies. Your reviewer also wonders if the author ever knew that the Indies was the recognized Spanish name of the continent during the age of its discovery.

It seems to us incredible that any one could make such a remark, seeing that every schoolboy knows the story of the naming of the West Indies, while our work refers over and over again to the fact that the continent was officially known in Spain as the Indias, — a general term including the East and West Indies, which contained a large number of countries.

When a work bases a discovery on the evidence of standard authorities, the impartial critic who is not convinced will point out where the evidence is defective. This is the law of logic, which a scholar cannot ignore. But when an author who translates his original evidence from Italian, Spanish, French, German, and Latin, finds himself designated under the clownish epithets of 'half-learned wanderers,' 'happy enthusiasts,' 'erratic followers,' etc., we will leave it to the public to say whether that is an impartial, fair, or scholarly critique, or whether it does not look like the work of some little publisher, whose history — always for sale — tells another story.

The great Baron de Humboldt says that Amaraca-pana was the first Spanish settlement on the mainland. This was in 1502, fiveyears before the pamphlet of St. Die proposed the name of Amerigo Vespucci,' who sailed into Amaraca-pana on his first visit, under command of Ojeda, to the New World, and which was the only place where they were favorably received, and treated as if they were angels. So says the royal Spanish historian Herrara, in quoting Ojeda himself; and the Isle of Tamaragua, on the first standard map of the continent, published in 1508, was evidently intended for Amaraca or America, which was long considered an isle. Here is positive evidence, by well-known authorities; and whoever is not convinced should point to evidence of a better explanation, or show cause why ours is insufficient; doing so in the language to use your reviewer's own words of a "sober historian." T. DE ST. BRIS.

New York, June 30. [Our correspondent has evidently failed to read the review carefully.- ED.]

FRIDAY, JULY 13, 1888.

NO SCIENTIFIC REPORT published by the government this year has been more important than that just made by Dr. J. J. Kinyown, assistant surgeon in the Marine Hospital Service, upon the germicidal powers of the different methods of disinfection practised under the direction of the Louisiana Board of Health at the quarantine station below New Orleans. The report is important, not only because it shows the degree of protection against the importation of infectious diseases through the important port of New Orleans; but also, since the methods of disinfection practised at other quarantine stations are similar to those in use there, the experiments show approximately the efficacy of each mode of disinfection, and suggest changes that should be made in their use. The three methods of disinfection tested were by the use of bichloride-ofmercury solution, the application of dry and moist heat, and fumigation with sulphur dioxide. Dr. Kinyown finds the first of these methods defective, because of the difficulty of getting the disinfecting-agent into cracks and corners, carpets, rubber goods, the under sides of decks, and into lockers, etc. He discovered in all these localities and articles that the micro-organisms existing before the disinfection had not been destroyed, and he found them as plentiful on the floor of the forecastle of one ship, that was exceptionally filthy, after it had been drenched with bichloride of mercury for an hour, as before. Dr. Kinyown recommends, that, in order to make this mode of disinfection more effectual, the bichloride of mercury be applied with a spray produced by a connection with a steamboiler, and that it be applied after fumigation by sulphur. The results from the application of dry and moist heat were the most satisfactory of all. Cultivations of various disease-germs exposed to a dry heat of 80o C., and afterwards to steam at a temperature of 100° C., were, with few exceptions, destroyed. Dr. Kinyown thinks, that, in order to secure absolute protection, the heat should be made greater and the time of exposure increased. In eleven experiments seventy-four disease-germs were placed in vessels among articles to be disinfected by the use of sulphur dioxide, but only sixteen of the whole were destroyed, or less than twenty-two per cent. Dr. Kinyown has very little to say about this method of alleged disinfection, except to recommend that the sulphurous fumes be applied in larger quantities, and confined in the compartments to be disinfected a longer time. But he reports his experiments in full, and lets them speak for themselves. The net result of these tests is to show that some disease-germs escape even when the most effectual modes of disinfection practised at quarantine below New Orleans are resorted to, and that less than one-fourth of them are killed when the least effective method is used. We assume that quarantine and city health officers everywhere will profit by the suggestions of this report, and that the public will be better protected in the future than in the past.

AT THE RECENT MEETING of the Massachusetts Assembly of the Agassiz Association in Boston, Prof. W. O. Crosby called attention to the fact that Mr. Harlan H. Ballard, the president of the association, in the 'Three Kingdoms' and elsewhere, has rightly emphasized the importance of studying the local natural history, and explained that this is especially desirable for the department of geology and mineralogy, since the rocks and minerals are in most

parts of the country, and especially in New England, much more localized than the fauna and flora. Thus, while the animals and plants must always change gradually from place to place, and may be nearly the same for an entire State, the geological features, the rocks and minerals, change very abruptly, and sometimes completely, as we pass from one formation to another; so that adjoining towns and neighborhoods are sometimes as strongly contrasted in their mineralogy and geology as the most distant parts of the earth. It will be readily seen that where this is true it is particularly desirable that each chapter should give attention chiefly to its own field; and interesting results may be expected from the presentation and comparison, at these annual meetings, of the work done in the different parts of the State. In this way each chapter will gain not only a valuable training in observation, but also that real and satisfactory knowledge of the local geology which can be obtained only through original study; while through the interchange of results and ideas the field is broadened, and the methods of work gradually improved. Professor Crosby spoke further as follows: "During all the time that I have been conducting the lessons in elementary and determinative mineralogy, I have felt that we should realize more fully the ideal plan of work for the Agassiz Association, if I could co-operate with members and chapters in the study of their local geology and mineralogy. Of course, it would be preposterous for any one to propose to do this for the entire organization. Not to mention other difficulties, such as the time required, it would be out of the question for any one specialist to have that detailed knowledge of the geology of the entire United States which would be required for the successful operation of such a plan. The organization of the Massachusetts Assembly has, however, suggested to me that I might, perhaps, be of some real assistance in this direction to the Massachusetts chapters. But, in offering to assist those who are really in earnest, I have no thought, of course, of pre-empting the field, or excluding other geologists. I simply desire to say that I, for one, shall be glad, so far as my time and ability will permit, to render such assistance as may be needed. I can help you sometimes in the determination of specimens; although it is to be hoped, for your own sakes, that you will heed Mr. Ballard's advice to exhaust your own resources before applying for such aid. I can, perhaps, offer useful suggestions as to the best plans for work in particular localities, and may be able to put you in the way of getting the necessary maps, etc., for the representation of your results. Lastly, though I can imagine that Professor Hyatt would advise me to proceed very slowly here, I can often aid you in finding what has been published on the geology and mineralogy of the different sections of the State. I shall, however, be very reluctant to do any thing in this direction in advance of good, original work in the field. The literature of your field would at first, in most cases, be only a hinderance to good work. It is to be hoped that every year you will bring your best results to these meetings, not merely brief reports of what you have worked at, but the work itself. Your principal reward will, of course, be the training and knowledge gained, and the satisfaction of having done good work. But it would be very strange indeed if such an exhibit of a year's results did not reveal something new to science, and worthy of publication; and this is another direction in which we should be glad to lend a hand." No chapter in Massachusetts can afford to neglect so rare an opportunity as Professor Crosby offers. Will not geologists in other States take a hint from this wise and generous method of encouraging this important branch of study in a practical manner?

METHODS OF DISINFECTION.

AT the request of the State Board of Health of Louisiana, that a test be made of the efficiency of the modes of disinfection employed by that board, Dr. Hamilton, surgeon-general of the Marine Hospital Service, detailed Assistant Surgeon J. J. Kinyown, last spring, to make the investigation. Dr. Kinyown's full report is published in the Weekly Abstract for June 29, and is so interesting and important that copious extracts from it are given below.

After describing the quarantine station and hospital below New Orleans, at which he arrived May 6, Dr. Kinyown makes full quotations from the brochure of Dr. Joseph Holt, ex-president of the Louisiana Board of Health, entitled The Quarantine System of Louisiana: Methods of Disinfection Practised,' to show the manner in which it is claimed that the germs of disease are destroyed in the baggage of passengers and crew of vessels, the cabin, deck, hold, and cargo. It is unnecessary even to make an abstract of these passages, since the modes of disinfection used are sufficiently indicated by Dr. Kinyown's own remarks and the reports of the experiments he conducted. It is sufficient to say that three methods of disinfection are described, that by the application of bichloride of mercury, fumigation with sulphurous oxide, and by applications of dry and moist heat.

Testing the efficacy of the methods practised and materials used in the disinfection of ships, cargo, and baggage," etc., says Dr. Kinyown, "was with special reference to the germicidal powers for which it is claimed.

Accordingly, before leaving New York, a large number of cultivation-tubes were prepared, containing blood-serum, peptone gelatine, agar-agar, and rags. A large number of these were inoculated from pure cultivations of the micro-organisms here mentioned; viz., spirillum choleræ Asiaticæ, spirillum Finkler-Prior, bacillus anthracis, bacillus typhi abdominalis, bacillus coli communis (Hueppe), bacillus murissepticus, bacillus pneumoniæ (Friedlander), bacterium of yellow-fever (Finlay), staphylococcus pyogenes albus, staphylococcus pyogenes aureus, streptococcus erysipelatus.

"Several of the series of above-named micro-organisms were obtained of Dr. T. M. Prudden; also one specimen of the micro-organism claimed to be the cause of yellow-fever, by Dr. Finlay of Havana, Cuba; another of the same organism was furnished by Dr. S. T. Armstrong, who had only a few days prior to my departure received it from Dr. Finlay.

"Whether the organism referred to is the cause of yellow-fever, we leave for others to confirm or disprove.

"In carrying out the following series of experiments, it was intended to show whether the process of disinfection applied to such vessels was sufficient to destroy the growth of these micro-organisms; and in but few instances was the process varied or the time lengthened from that which is practised from opening of the quarantine season to June 1, when the time is lengthened to five days. It was also for the purpose of deciding whether the time imposed on vessels prior to June I was sufficient for the prevention of epidemic disease.

"In carrying out these experiments, several classes were conducted at the same time, and, to have them correspond with the description of the machinery, etc., the same order will be followed.

"Since the opening of the season, vessels engaged in the fruittrade, and plying between ports subject to quarantine, are not subjected to the same treatment as others. Should they have any passengers aboard who have with them any baggage or articles of clothing save what they wear, they are compelled to stop at the upper station, where the baggage of passengers, crew, ship's linen, etc., are subjected to the steaming process, while the cabin and deck are washed down with bichloride solution.

"If no baggage is aboard, they are given pratique to the city, where the cargo is discharged, and vessel cleansed by washing the deck and burning sulphur in the hold. The quantity of sulphur used was not learned.

This is invariably done before the vessel is treated to sulphur dioxide, in order to delay it as little as possible.

"The flat surfaces of the decks are thoroughly washed with a rose sprinkler, but around among the corners, hatches, or perchance hogsheads of sugar that are sometimes on deck, the process is defective, because a great many places are not reached. The same can be said of the disinfection of the cabin, lockers, etc.: only a partial disinfection is accomplished; for, to wet all surfaces, with the present arrangements it would be necessary to almost submerge them with the solution. The carpets, rugs, rubber and leather goods, trunks, and valises are sprinkled with the same bichloride solution.

"Several experiments were made upon the goods, clothing, and surfaces thus treated; and it was found that the solution did not cover all the surface, for portions of carpets, scrapings from floor and under side of the forecastle, deck, etc., when placed upon sterilized nutrient media, showed evidences of germ-development. No apparent difference could be noticed between portions removed from the floor of the forecastle after being saturated for one hour with the bichloride, and other portions of the same that had not been reached by the solution. The last can be explained by the fact that the forecastle was in an extremely filthy condition, and, there being such an abundance of organic matter, the bichloride was rendered inert.

For the general application of this solution to the ship, especially to cabin, carpets, etc., we suggested that a spraying apparatus be substituted, made by leading a rubber hose from the boiler of the tug, and connecting it with the supply-pipe of the bichloride solution in such a manner as to make a Richardson's spray-producer' on a large scale, so that by its use all surfaces, cracks, etc., can be thoroughly and evenly wetted.

"Former experience teaches that placing dirty and greasy clothing in the heating-chamber is not a safe procedure with the present apparatus, for to them have been traced the cause of fires breaking out during the steaming process. They are now left on deck and sprinkled with bichloride of mercury, in the following manner: One attendant stands ready with hose in hand, while another places the clothing to be thoroughly wetted down on the deck, turning them over from time to time, while the other plays a stream of bichloride upon them.

The car upon which the clothing, bedding, goods, etc., is placed for the purpose of transporting them to the steam-heating chamber is not disinfected before the goods are placed upon it to be taken back to the ship."

Seven tables are given for the purpose of showing the variations of temperature obtained in the heating-chamber, and Dr. Kinyown then proceeds to give detailed reports of the experiments he made. The first series was for testing the applications of dry and moist heat. He says:

"I was informed by Dr. Aby that his instructions from the board of health were to the effect that clothing, bedding, etc., after being placed within the chamber, should be raised to a temperature of 85° C., after which the steam should be turned on, and kept for twenty minutes after the thermometer indicates 100° C. This manner renders fire less imminent. The time of exposure of micro-organisms to the heating process was not varied from the prescribed rules, save in two instances.

"Cultivations of micro-organisms on various substances were placed, in each of the following experiments, in positions where the minimum heat was to be expected.

"EXPERIMENT No. 1.- Cultivation-tubes of peptone agar-agar inoculated with spirillum choleræ Asiaticæ, bacillus anthracis, bacillus typhi abdominalis, bacillus coli communis, bacterium of yellow-fever (?), were placed in a wire basket and hung in the compartment most distant from the boiler, and upon which but little clothing was hung. In sixteen minutes the temperature (dry heat) reached 79.4°, when steam was turned on and kept twenty minutes, cultivations removed, and inoculations made therefrom, the temperature being ascertained by placing a self-registering thermometer upon the surface of agar-agar within the cultivationtubes. Repeated examinations show all growths to have been killed.

aticæ on blood-serum, bacillus anthracis on agar-agar, bacillus typhi abdominalis on agar-agar, bacillus coli communis on agar-agar, bacillus pneumoniæ on agar-agar, bacterium yellow-fever (?) on agar-agar, staphylococcus pyogenes albus on blood-serum, staphylococcus pyogenes aureus on blood-serum, were suspended in among blankets and mattresses in a compartment near the boiler. A quarantine thermometer registered 88.8° dry heat in central chamber. Steam turned on, and kept forty-three minutes. Temperature among blankets fell to 82.5°. Inoculations made from these cultivations into peptone gelatine showed the bacillus anthracis and bacterium yellow-fever alive: all others were dead. The temperature was taken on the outside of the cultivation-tubes. "EXPERIMENT NO. 3. Chamber filled with goods, consisting chiefly of bedding and clothing of the crew. The articles were not hung closely together, as the chamber was filled to only threequarters of its capacity. Cultivations of spirillum choleræ Asiaticæ, spirillum Finkler-Prior, bacillus anthracis, bacillus pneumoniæ, bacillus typhi abdominalis, bacillus coli communis, bacterium yellow-fever (?), staphylococcus pyogenes albus, staphylococcus pyogenes aureus, were placed in a basket and arranged upon and between mattresses. Thermometers being placed among cultivations, temperature registered 85.5° C. dry heat in centre chamber. Steam turned on, and allowed to remain twenty seven minutes. All micro-organisms dead except those of bacillus anthracis and bacterium yellow-fever. Thermometer among cultivations indicated 95.5° C.

"EXPERIMENT NO. 4.- Chamber partially filled, compartment containing principally the mattresses and clothing of the crew. A hair mattress was opened, and tubes containing cultivations of spirillum choleræ Asiaticæ, spirillum Finkler-Prior, bacillus anthracis, bacillus typhi abdominalis, bacillus coli communis, bacterium yellow-fever, bacillus murissepticus, staphylococcus pyogenes albus, staphylococcus pyogenes aureus, were placed within, and exposed to moist heat for twenty-five minutes. A self-registering thermometer placed among tubes indicated 75°. Examination of growths showed those of bacillus anthracis, bacillus murissepticus, and bacterium yellow-fever to be alive: all others were killed.

"EXPERIMENT No. 5. — Chamber well charged with goods. A series of cultivation-tubes containing rags (both cotton and woollen) that had been inoculated with bacillus anthracis, bacillus typhi abdominalis, bacillus pneumoniæ, staphylococcus pyogenes albus, staphylococcus pyogenes aureus, were placed in among mattresses and blankets, and exposed for twenty minutes to moist heat. Temperature indicated, 62.5° C. Examination showed all growths dead save that of anthrax.

"EXPERIMENT No. 6.- Clothing and bedding of steamship 'Saturnina,' from Cuba to New Orleans, placed in heating-chamber; all compartments filled. Owing to the uncleanness of the crew's bedding, we suggested that a longer time be given in the steaming process. Cultivations on agar-agar of spirillum choleræ Asiaticæ, spirillum Finkler-Prior, bacillus anthracis, bacillus typhi abdominalis, bacillus pneumoniæ, bacillus coli communis, staphylococcus pyogenes albus, staphylococcus pyogenes aureus, were placed in the compartment, arranged on mattresses, and surrounded by pillows. Temperature of middle chamber (quarantine thermometer), 76.6° C. Left for fifty-five minutes. Thermometer among cultivations indicated 67°. Inoculations show all killed except bacillus coli communis and bacillus anthracis.

"EXPERIMENT No. 7. - Chamber was lightly charged, several panels in each compartment being empty. Cultivations made upon rags of the following: spirillum cholera Asiatica, bacillus typhi abdominalis, bacterium yellow-fever, staphylococcus pyogenes albus, staphylococcus pyogenes aureus. These were suspended among clothing, chiefly underwear, and allowed to remain forty minutes. A thermometer placed in a tube containing similar media registered 99°. Inoculations from the tubes show that all have been killed except the bacterium of yellow-fever.

"EXPERIMENT No. 8. — Chamber filled with goods, — bedding and clothing. Cultivations of spirillum choleræ Asiaticæ, bacillus anthracis, bacillus typhi abdominalis, bacillus coli communis, bacterium yellow-fever, staphylococcus pyogenes albus, were placed in heating-chamber, in its centre, arranged upon blankets and clothing. These were subjected to moist heat for forty minutes. Tem

perature indicated near cultivations was 69°. The bacillus anthracis, bacillus typhi abdominalis, bacillus coli communis, and staphylococcus pyogenes albus were found to be alive.

The quantity of sulphur consumed in the fumigation of each vessel is from 100 to 400 pounds, according to the size of the vessel. Those arriving at quarantine during our stay at the station varied from 100 to 2,000 tons burden. About 100 pounds of sulphur are consumed in an hour, and form about 1,170 cubic feet of sulphur dioxide. If, as is claimed, 180,000 cubic feet of air per hour be driven into the hold or compartment of a vessel, the strength of the gas would be approximately .6 per cent.

"That that quantity of air is not driven into the hold is proven by the fact that in quite a number of volumetric analyses, made on various vessels at the close of fumigation (for the purpose of determining the quantity of sulphur dioxide present), it was shown that there are from 2 to 6 per cent to the 100 pounds of sulphur, the capacity of the compartments being about the same, viz., 20,000 cubic feet. This does not represent the full amount of the gas generated, for in all vessels there is constantly present a certain amount of moisture, which absorbs the gas.

"In the generation of the sulphur dioxide there is formed in the 'battery' a certain amount of nitrous oxide, and, the gas being quite hot (130°) as it enters the vessel, every factor is present for the rapid production of sulphuric acid. The greatest percentage of gas was found in holds containing coffee, still less in sugar, and least in those vessels that had been treated with the bichloride solution previous to fumigation. In these the percentage was notably diminished (2 per cent), the gas being absorbed by the wetted surfaces, also uniting with the mercuric salt, forming a compound which impairs germicidal power of both, and destroys penetrating properties of the gas.

"We were informed that it was the custom formerly to put the exhaust-fan in operation for an hour before, driving pure air into the hold, thus aerating the vessel and cargo before fumigation was commenced. This was not put in practice during our stay. Ves sels hailing from ports known to be infected are treated to a larger quantity of gas, 200 pounds or more of sulphur being used to each compartment.

In testing the germicidal power of the fumigating process it was for determining whether the short time of detention practised prior to June was of sufficient duration to insure complete disinfection of vessel and cargo.

Where the compartments are empty or communicating with the engine-room or chain-locker, the hatches are not sealed by the customs authorities, and there is no assurance that the sulphur fumes remain longer than a short time after the disinfection is finished.

"It was noticed in several instances where the forward hatch communicated with the chain-locker or engine-room, that the hatches were removed immediately after fumigation, and a wind-sail put in place for the purpose of driving out the fumes, so as to enable the vessel to leave for New Orleans as soon as possible.

"Vessels having their hatches sealed are insured of at least fifteen hours' disinfection. The forecastle, after being thoroughly wetted with bichloride solution, is treated to the 'pot plan,' the longest period of time being three hours, after which it was immediately permitted to be thrown open by the crew. The following experiments were made:

EXPERIMENT No. 1. - Spanish bark Pedro,' from Havana to New Orleans. Thoroughly wetted down with bichloride solution. A basket containing cultivations on agar-agar that had been inoculated fifteen days previously with spirillum Finkler-Prior, bacillus anthracis, bacillus typhi abdominalis, bacillus coli communis, bacterium yellow-fever, was placed about sixty feet from the hatch, where the fumigating-pipe enters. The cotton plugs were removed from the test-tubes. These were left for a period of ninety minutes, the time occupied in the fumigation. One hundred and fifty pounds of sulphur were used. Inoculations made from time to time from these tubes show that all the growths were not influenced by the exposure.

“EXPERIMENT No. 2, SO,.- Steamship 'Morgan.' Rear hold compartment filled with sugar in sacks. A basket containing cultivations prepared for exposure was placed in the hold about six

teen feet distant from the hose leading into the compartment; tubes containing spirillum Finkler-Prior, bacillus anthracis, bacillus pneumoniæ, bacillus murissepticus, bacterium yellow-fever (?), staphylococcus pyogenes albus, staphylococcus pyogenes aureus. Time of exposure, two hours and twenty minutes. One hundred and fifty pounds of sulphur used. Owing to the character of cargo, no bichloride solution was used. Inoculations made from growth of each micro-organism show no effect upon them.

EXPERIMENT No. 3, SO,.- Two baskets were prepared for placing in the forward hold of steamship Morgan;' capacity, 101 tons; cargo of sugar in bags; basket No. 1 containing cultivations of spirillum cholera Asiatica on blood-serum and rags, bacillus coli communis on agar-agar, streptococcus erysipelatus on blood-serum; basket No. 2, spirillum Finkler-Prior, bacillus anthracis, bacillus coli communis, bacillus pneumoniæ, bacterium yellow-fever (?).

"Basket No. I placed fifteen feet from pipe; basket No. 2, thirty feet from pipe. Cultivations exposed for one hour and twenty minutes; fumigation lasted one hour. About 100 pounds of sulphur used. Cultivations had to be removed, as the vessel was ready to leave the dock; forward hatch was not sealed. All cultivations alive; no inhibitory effect noted.

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EXPERIMENT NO. 4. - Steamship Floridian,' from Colon to New Orleans, having but little freight; several compartments empty. Cultivations of spirillum choleræ Asiaticæ on blood-serum, spirillum Finkler-Prior on blood-serum, bacillus anthracis on agaragar, bacillus typhi abdominalis on agar-agar, bacillus murissepticus on blood-serum, bacillus cholera nostras on agar-agar, staphylococcus pyogenes albus on agar-agar, staphylococcus pyogenes aureus on agar-agar, were placed in forward compartment (empty). Compartment fumigated for two hours, and allowed to remain for eight hours and thirty minutes. Inoculations were made from time to time, and it was found that those of choleræ Asiaticæ, Finkler-Prior, staphylococcus pyogenes alba and aureus, and bacillus murissepticus, were dead. No effect was noted in any way upon anthrax, typhoid, and cholera nostras.

EXPERIMENT No. 5. Cultivations prepared by placing a small quantity of sterilized cotton in test-tubes, and moistening it with a small quantity of distilled water. The cotton was then infected with several growths of the following: spirillum choleræ Asiaticæ, spirillum Finkler-Prior, bacillus anthracis, bacillus coli communis, bacterium yellow-fever (?), staphylococcus pyogenes albus, staphylococcus pyogenes aureus.

"These were placed in an empty compartment that had been thoroughly washed down with the bichloride solution. About 125. pounds of sulphur used. Volumetric examination of gas shows 8 per cent. Time cultivations were exposed, three hours and fifty minutes. Only that of choleræ Asiaticæ was killed.

"EXPERIMENT No. 6. - Cultivations on agar-agar, made only twenty-four hours before, of spirillum choleræ Asiaticæ (2), spirillum Finkler-Prior, bacillus anthracis, bacillus typhi abdominalis, bacillus coli communis, bacillus pneumoniæ, bacterium yellowfever (?), staphylococcus pyogenes albus, staphylococcus pyogenes aureus; also cultivations on cotton and woollen rags of spirillum Finkler-Prior, bacillus coli communis, bacillus pneumoniæ, bacillus typhi abdominalis, bacillus murissepticus, staphylococcus pyogenes aureus, streptococcus erysipelatus.

"Both series were placed in the forward compartment of steamship Lizzie Henderson,' a small steamer plying between Tampa and New Orleans. After fumigation the hatch was battened down, and the cultivations left until the vessel arrived in New Orleans, when they were taken out and inoculations made therefrom into fresh agar-agar. Time of exposure, twenty-four hours. Of the growths upon agar-agar, those of bacillus pneumonia, FinklerPrior, and choleræ Asiaticæ were killed. None of those on rags affected.

to the city, the hatch was thrown open; and nine hours thereafter, on arrival in New Orleans, the basket was removed. All germs found living.

"EXPERIMENT No. 8. - Potato placed in large test-tubes, and inoculated with spirillum choleræ Asiaticæ, spirillum Finkler-Prior, bacillus anthracis, bacillus typhi abdominalis, bacillus coli communis, bacillus pneumonia, bacterium yellow-fever (?), staphylococcus pyogenes aureus.

"These were placed in a basket, and wrapped in an old mattress, which was lowered into an empty compartment of the steamship 'Saturnina.' Fumigated for two hours. 200 pounds of sulphur used. The mattress was taken out four hours after. All growths dead except anthrax, typhi abdominalis, staphylococcus pyogenes aureus, cholera nostras, and yellow-fever. Test-tubes containing agaragar and gelatine show that the gas in the above-mentioned time penetrates to the depth of three-quarters of an inch. Percentage of gas, 6 per cent. Hatch sealed by customs-officer.

"EXPERIMENT No. 9. - Recent cultivation on agar-agar, of spirillum cholera Asiaticæ, spirillum Finkler-Prior, bacillus anthracis, bacillus coli communis, bacterium yellow-fever (?), staphylococcus pyogenes albus, were placed in hold of bark Antonio Georgio,' in ballast, from Havana to New Orleans. Ballast and interior of hold well washed down with bichloride solution. Fumigation, an hour and a half. 150 pounds of sulphur used. Time of exposure, two hours. No effect on the organisms.

"EXPERIMENT No. 10. — A basket containing surface cultivations on agar-agar, of spirillum choleræ Asiaticæ, bacillus anthracis, bacillus typhi abdominalis, bacillus coli communis, bacillus murissepticus, staphylococcus pyogenes albus, bacterium yellow-fever, was placed in forward compartment of steamship Inventor,' down under bags of coffee, being well covered up. Fumigation lasted four hours. 275 pounds of sulphur consumed. Hatch was then closed for seven hours, when it became necessary, on account of the chain-locker communicating with the compartment, to open the hatch and place wind-sail in position, in order to drive out the gas, so that anchor could be raised. The basket was removed on arrival in New Orleans, twenty hours after, at which time the fumes were still quite strong. Examination showed all cultivations to be alive, though slight inhibitory effect was noticed.

"Cultivation-tubes containing agar-agar and gelatine that were exposed at the same time to SO, completely inhibited the growth of all micro-organisms tested.

"EXPERIMENT NO. 11. - Cultivations on agar-agar, of spirillum choleræ Asiaticæ, bacillus anthracis, bacillus typhi abdominalis, bacillus murissepticus, staphylococcus pyogenes albus, placed in rear compartment of steamship Inventor,' at a point farthest from the entrance of SO,. Cargo, sugar. Fumigation for four hours and thirty minutes. 300 pounds sulphur used; hatch then sealed. On arrival in New Orleans, twenty-two hours later, the hatch was opened and an attempt made to remove the basket, but the fumes of the gas were so strong that this could not be accomplished for two hours and a half. Examination of the cultivations showed that all micro-organisms were dead except that of anthrax. "Cultivation-tubes containing agar-agar and gelatine showed the same inhibitory power as in the preceding experiment.

"EXPERIMENT NO. 12. — A litre of air was collected in sterilized vessels before and after the application of sulphur dioxide. Examination was made for the purpose of determining whether or not the gas exercised a germicidal effect on the micro-organisms of the air in the ship's hold.

A series was collected that had been exposed one, two, four, and eight hours respectively, samples having been collected previous to application of the gas for the purpose of making control observations. None of the series showed diminution in number. "EXPERIMENT No. 13. Cultivation-tubes containing peptonized agar-agar, gelatine, and rags, exposed for one, two, and four hours, show a decided inhibitory effect on all micro-organisms that were tested. Those exposed for six, eight, and twenty hours to sulphur dioxide killed all non-spore-bearing germs.

It has been our intention to show by the foregoing observations upon the methods practised in carrying out the present system of quarantine at this station whether or not it is efficient; if not, to show its defects, and how remedied.