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PERU, CHILI, AND UNITED STATES. PHOTOGRAPHY, IMPROVEMENTS IN. 747

offenses avoided ; that questions growing out of fended, the President prefers that he shall himself dethe suppression of the Calderon Government termine, atter report has been made to him, whether could be attended to at Washington; and that there is or is not cause for offense. It is also the

President's wish that you do not visit (although init was preferable that he should not visit Bue- dicated in your original instruction that you should nos Ayres on his way home. On the 9th of do so) as the envoy of this Government, the Atlantic January, 1882, Secretary Frelinghuysen wrote republics after leaving Chili. to Señor Martinez, the Chilian Minister at of the earth, and the President wishes hereafter to

The United States is at peace with all the nations Washington, acknowledging receipt of a pote determine whether it will conduce to that general from the latter of December 28th, in which he peace, which he would cherish and promote, for this gave his views as to the condition of Peru, de- Government to enter into negotiations and consultarived from his latest intelligence. Secretary tion for the promotion of peace with selected friendly

nationalities without extending a like confidence to Frelinghuysen continues his letter as follows:

other peoples with whom the United States is on I was much gratified yesterday with the assurances equally friendly terms. If such partial confidence which you gave me in our personal interview that would create jealousy and ill-will, peace, the object your Government, in the arrest and imprisonment of sought by consultation, would not be promoted. The Calderon, was in no way instigated by an upfriendlyprinciples controlling the relations of the republics feeling toward the United States. If you feel yourself of this hemisphere with other nationalities may, on at liberty to renew that assurance in writing, I shall investigation, be found to be so well established that be still further and greatly obliged by your doing so. little would be gained at this time by reopening a Such a communication, written in the friendly spirit subject which is not novel. The President, at all which marked your verbal communications, will tend events, prefers time for deliberation. to promote that friendly feeling which is so desirable among American republics.

There is considerable correspondence relaOn the 10th of January Señor Martinez re- want of space makes it necessary at present to

tive to the Cochet and Landreau claims, but a plied to this letter in a similar friendly spirit. On January 9, 1882, Secretary Frelinghuysen

pass it over. wrote to Mr. Trescot as follows:

PHOTOGRAPHY, IMPROVEMENTS IN. The

collodion process of photography, which has SIR: Since you received your instructions on your been in use for thirty years, is being generally departure as special envoy to Chili, Peru, and Bolivia, I have sent you by cable two instructions. As I have supplanted by the new dry process, in which not heard of your having received them, and to make gelatine is employed to hold in suspension their purport more intelligible than the brevity of a the sensitive salts of silver. The preparation telegram would permit, I send this, stating the proper of the gelatino-bromide plates is conducted as modifying them, and indicating how they are to be follows: To a solution of fine gelatine in waexecuted.

ter is added bromide of potassium or bromide The President wishes in no manner to dictate or of ammonium. In another vessel nitrate of make any authoritative utterance to either Peru or silver is dissolved in water. In a room lighted Chili as to the merits of the controversy existing be only through dark ruby glass the solution of tween those republics, as to what indemnity should silver salt is gradually stirred into the mixture be asked or given, as to a change of boundaries, or as to the personnel of the Government of Peru.' The of bromide and gelatine. When great sensiPresident recognizes Peru and Chili to be independent tiveness is required, it is to be kept in a fluid republics, to which he has no right or inclination to condition for from one to four days. Ordinarily dictate. Were the United States to assume an attitude it is left only a few hours, and can be more of dictation toward the South American republics, even for the purpose of preventing war, the greatest rapidly evaporated by heating. The emulsion of evils, or to preserve the autonomy of nations, it is next freed from the nitrate of potassium or must be prepared by army and navy to enforce its ammonium by breaking it into pieces after it mandate, and, to this end, tax our people for the ex- has been allowed to set in a deep dish, and clusive benefit of foreign nations. The President's policy with the South American republics and other washing it in several changes of cold water. foreign nations is that expressed in the immortal ad- It is then melted into plates, after being drained. dress of Washington, with which you are entirely fa- After the plates have been coated and dried miliar. What the President does seek to do is to ex- they are ready for use. These dry plates can tend the kindly offices of the United States impartially be kept any length of time without losing

Plates which are thus other he seriously laments; and he considers himself their sensitiveness. fortunate in having one so competent as yourself to made in quantity and are always ready can be bring the powers of reason and persuasion to bear in employed in out-of-door and amateur work, seeking the termination of the unhappy controversy; and for the many scientific uses of photogand you will consider as revoked that portion of your raphy in which the troublesome wet process, original instruction which directs you, on the contingency therein stated, as follows:

requiring the use of chemicals and a dark ? You will say to the Chilian Government that the chamber, would be difficult or impossible. The President considers such a proceeding as an inten- convenience of the gelatine and bromide proctional and unwarranted offense, and that you will communicate such an avowal to the Government of

ess is not its only advantage. The images the United States, with the assurance that it will be rendered are as clear and perfect as any obregarded by the Government as an act of such un

tained from collodion plates, and the impresfriendly import as to require the immediate suspension sions are formed in the camera in one sixth to of all diplomatic intercourse. You will inform me one tenth the time of exposure. The action immediately of the happening of such a contingency, and instructions will be sent to you."

on the most highly sensitive gelatine plates is Believing that a prolific cause of contention between practically instantaneous, pictures having been two nations is an irritability which is too readily of- taken in ito of a second.

PHYSIOLOGY, RECENT. Physiological sci- the pressure to which the portion of tissue exence has made great advances under the syg- amined was subjected was raised, the current tem of specialized minute investigation of the of blood through the smaller arterioles lost the different tissues and organs of the body and equable character which it normally presents, their functions which is now very generally and a rhythmic variation in rapidity, a pulse applied. Nearly every vessel and nearly every which could not be detected in the small arterfluid of the body has been subjected under this ies while the tissue was uncompressed, each system to a most rigid and searching micro- increase corresponding with a heart-beat, bescopic, chemical, and dynamic examination, came more and more evident. The blood-flow and is thereby being made to disclose the most through the capillaries also became more and intimate secrets of its structure and function. more pulsatile in character, and, in that part of Dr. Ferrier and Professor Yeo bave added to the capillary plexus which lies nearest the arthe clearness of the evidence of the localization teriole whence the blood came, a temporary of function in the cortex of the brain from ob- arrest of circulation took place when a cerservations made in their experiments on monk- tain pressure, which was different at different eys. They are able, after having effected a lo- points, was reached. It was also found that calized or limited lesion by means of the gal- the capillaries which first cease to convey blood vanic cautery of the surface of the brain, to under these circumstances are not always the predict the precise phenomena of paralysis same, a fact which can not be easily explained which will occur. On microscopical examina- otherwise than by assuming that the relative tion after death following these phenomena, diameters of the capillaries have changed strands of fibers proceeding from the damaged that some vessels have expanded while others parts of the cortex may be traced down to the have contracted in the interval between two motor or sensory ganglia at the base of the observations. In favorable instances such a brain, and thence downward through the spi- change in the diameter of the different vessels dal cord to the muscles paralyzed by the lesion. can be verified with the help of a micrometer. Exner, who has been engaged in considering the small veins, or venous rootlets, show under localization in the function of the brain by the the application of pressure a diminution of di. aid of the phenomena presented by patholog- ameter, often to one third of the original caliical changes, has satisfied himself by that meth- ber, accompanied with an increase in the flow od of the existence of very limited areas on the of blood through their interior. The flow of surface of the brain, destined to receive im- blood in the veins becomes accelerated with pressions and original motor impulses. Cou- each pulse-wave in the arterioles, and slowed ty's researches on the same point, published between the beats; and when the blood no in Brown-Séquard's “ Archives," appear to be longer advances in the arteriole, the correaltogether opposed to Ferrier and Hitzig's con- sponding vein or veins become empty or col. clusions.

lapsed. It has long been known that capillary Professor Charles S. Ray, assisted by G. H. vessels may present considerable variations in Lewes, student, and J. Graham Brown, M.D., diameter at different times, and these variahas pursued an investigation of the blood-press- tions have been ascribed to the elasticity of ure and its variations in the arterioles, capilla- the capillary walls. Professor Ray's esperiries, and smaller veins. Attempts had been ments, however, tend to show that modificapreviously made to measure the pressure of the tions of the intra-capillary pressure, much greatblood in the capillaries by N. V. Kries, whose er than those which can normally occur, influexperiments were made upon the vessels of the ence but slightly the caliber of the capillaries, human skin, particularly on that part of the and lead almost inevitably to the conclusion distal phalanx of one of the fingers inmediate- that the capillaries are contractile as well as ly behind the nail. The method he employed elastic. To the question whether this conconsisted in pressing, by means of weights, a tractility resides in some anatomically differen. small glass plate of known area upon the por- tiated part of the capillary wall, or whether it tion of skin selected, and finding the weight be a property inherent in the wall as a whole, required to produce a distinct whitening of the the answer may be returned that capillary vescompressed as compared with the surrounding sels may be seen to vary greatly in diameter skin. It was assumed, in making these experi- without any localized contraction or expansion ments, that the pressure which sufficed to cause being visible; that the capillary tube expands an evident change in the color of the small or contracts as a whole, its diameter remainarea of skin lying under the glass plate, was ing equal throughout its whole length. The equal to the pressure of the blood in the capil- anæmia or absence of blood which is produced laries lying nearest the surface. This method on any part by pressure is followed, when the was applied with some satisfaction to the de- pressure is removed, by an excess of blood or termination of the relative values of pressure congestion, which gradually passes away. This under varied conditions. Professor Ray sought phenomenon has been proved not to reside in a more delicate method for the study of the any reflex action through the cerebro-spinal absolute values of the pressure by means of mi- vasomotor centers; hence attention is directed croscopic examinations of the web of a frog's to the probability of some peripheral vasomofoot. The first observations showed that as tor mechanism by which the degree of dilata

tion of the vessels of the skin is capable of be- the conclusion that the chief and not the bor. ing regulated independently of the cerebro-spi- der cells produce pepsin. This is confirmed nal vasomotor centers. It is not clear what is by Dr. Langley's comparison of the pepsin conthe nature of this mechanism, but it seems to tents of the different stomach regions in sevbe adequate to measure out the degree of dila- eral animals. In each case the amount of peptation according to the requirements of the tis. sin found bore no relation to the number of sues, and appears to be the same that is called border cells, but almost always varied directly into action under the application of irritants. with the number of chief cells. It was also The capillary vessels have been shown to be shown that in the different regions of the stomcapable of varying their diameters independ- ach of the rabbit most pepsin is found wbere ently of one another. The conclusion is logic- the granules are most numerous. It is now ally derivable that each capillary is capable of very generally accepted that pepsin exists in varying its caliber in accordance with the re- the gastric glands partly free and partly com. quirements of the tissues which it supplies with bined—i. e., partly as pepsin and partly as pepblood. To this automatic regulation of the sinogen. A series of experiments made with peripheral circulation Professor Ray is in- especial reference to this point has convinced clined to ascribe & function of great impor- Dr. Langley that pepsin, as such, does not extance, both from a physiological and a patho- ist in the living glands, but that in the animals logical point of view; and it appears that it is with which he worked, and probably in all principally, if not exclusively, in connection vertebrates, the gastric glands store up pepsinwith it that the contractility of the capillaries ogen and not pepsin. This is converted by comes into play.

hydrochloric acid into pepsin. As far as our Dr. J. N. Langley, of Trinity College, Cam- knowledge goes, rennet - ferment is found in bridge, has brought the subject of the histolo- greatest quantity where there is most pepsin, gy of the gastric or pepsin-making glands be- and both vary pari passu. Perhaps, suggests fore the Royal Society, in a paper in which he Dr. Langley, the granules of the chief cells may has sought to collate the proofs, from his exper- contain zymogen both of pepsin and of reniments, that the gastric glands in life contain net-ferment, and he offers this as a subject for no ferment, but much zymogen or substance further observation. In all the vertebrates in capable oi giving rise to ferment; that by far which the gastric glands have been carefully the greater part of the zymogen can be seen in examined in the living state, it has been found the chief cells in the form of granules; and that those gastric glands which produce most that during digestion the granules are usually ferment store up their zymogen in the form of used up in such a manner as to give rise to an granules. The ferment-forming cells consist outer non-granular and an inner granular zone of a net-work of protoplasm, inclosing a mass in the chief cells. These points, if proved, would of granules. It seems probable, on general establish fundamental resemblances in life-hab- grounds, that the cells should store up other it between the chief cells of the gastric glands antecedent substances besides zymogen, and of mammals, the cells of the gastrio glands of we are not without facts which will tell in the lower vertebrates, and the cells of the pan- favor of this view. In the saliva of many anicreatic gland. It was found that the chief-cell mals ferment is almost or entirely absent, but granules of some mammals are preserved by mucin and proteids occur.

We have some osmic acid, while those of others are not. The proof that mucin arises during secretion from examinations were made chiefly with prepara- the splitting up of an antecedent substance, tions of the former class, and were checked by mucigen, which is stored up in the cell ; in the comparison with glands in the fresh state; they serous salivary glands, and in the lachrymal related to the border cells and the chief cells glands, the occurrence of granules which are of different regions of the stomach. In both used up during secretion, just as are the granthe mouse and the mole, in the hungry state, ules of the pancreas or of the gastric glands, the chief cells are granular throughout; in the makes it extremely probable that in those glands digestive state, the chief cells have an outer some antecedents of the proteids found in the non-granular zone of from one third to one secretion, not the actual proteids of the secrehalf of the cell. In the Guinea-pig and the tion, are stored up. Apparently, then, a large rabbit the chief cells of the latter part of the number of gland-cells have the feature in comgreater curvature show few or no granules; mon that the cell protoplasm forms certain in the median part of the greater curvature the antecedent substances, which Dr. Langley proglands have usually an outer clear zone, which poses shall be called “mesostates," which it diminishes in passing toward the fundus, while stores up, and that are converted, when secrein the fundus and in the adjoining part of the tion takes place, into secretory products. In greater curvature the chief cells are granular the pancreas the chief mesostate is trypsinogen, throughout. During digestion an outer clear in the gastric glands it is pepsinogen, in the zone is formed in the glands of the latter part mucous glands it is mucigen, etc. of the fundus and the fore part of the greater Observations made Uffelmann on a pacurvature, while the cells of the rest of the tient upon whom gastrotomy had been pergreater curvature lose more or less completely formed, have indicated that no hydrochloric their granules. Heidenhain first announced acid is secreted during the earlier stages of

digestion, although that substance may some an experiment in which the diluted parotid extimes be found in the course of three quarters tract retained but a trace of its amylolytic of an hour or an hour after the ingestion of power when it was warmed for fifteen minutes food. The acid present was always lactic, with one tenth of its bulk of gastric fluid. even when the conversion of albumen into the destructive action of even very dilute peptone, and of starch into dextrine and sugar, acids was found to be extraordinarily rapid. was distinctly taking place. The observations The secretions from the pancreas and intestinal of Cash, made in Ludwig's laboratory, have glands are also capable of dissolving the gasshown that, contrary to the statements usually tric ferments, and owe their power chiefly to given in text-books, fats may be split up in the their alkaline salts. The action of these salts, stomach into the fatty acids and glycerine, as exemplified in sodium carbonate, is decided while an acid, perhaps the lactic, is formed. and rapid. It is auginented when trypsin is also It is a remarkable fact that although after the present, but the effect of trypsin alone is less full digestion of every meal a considerable marked. The rennet ferment is, like pepsin, quantity of peptones must be introduced into destroyed rapidly at the body temperature by the blood, none passes off by the kidneys; yet sodium carbonate, and to some extent by trypif solutions of the peptones be directly in- sin; whence we may conclude that it also loses jected into the blood-vessels, from 60 to 70 its ferment power irrecoverably in the small per cent is rapidly eliminated by these organs. intestine. Since trypsin is destroyed both by Hofmeister, finding peptone abundant in the hydrochloric acid and by pepsin, the adminiswall of the intestine, has arrived at the con- tration of pancreatic extract with food in clusion, from his experiments on this point, medical practice to aid digestion is of more that the numerous nuclei and cells which oc- than doubtful benefit; for little, if any, trypcupy the meshes of the adenoid tissue of the sin can pass into the duodenum to exercise intestinal mucous membrane fix the peptones, a digestive function there. An extract of the and thus enable them to enter the blood- pancreas rapidly loses its amylolytic power current without the danger of being excreted when warmed with dilute hydrochloric acid, by the kidneys. The white corpuscles, on this more rapidly than does trypsin under similar view, act as carriers of nutritive material to all circumstances, but apparently less rapidly than parts of the body, just as the red corpuscles does the amylolytic ferment of the parotid. act as carriers of oxygen.

Recent researches reported by M. Dufresne During digestion much saliva, gastric juice, throw new light on the relations of ptyalin, and pancreatic juice flow into the alimentary diastase, and the gastric juice. It has been a canal, each secretion bearing with it a con- subject of debate whether the saliva is destroyed siderable quantity of ferment, chiefly either in the gastric juice, or continues in the stomach amylolytic or proteolytic. Very little, how- its action on starch. M. Đufresne's experiever, is known of the fate of these ferments; ments prove that the saliva is paralyzed in pure for the little of them that may be found in the gastric juice, but recovers its action in the fæces and urine makes but a small fraction of mixed gastric juice and in the duodenum, and the whole amount which is received by the is capable of continuing the process of sacchaalimentary canal during digestion. Dr. J. M. rification; while diastase is irrecoverably deLangley has made investigations on this sub- stroyed in hydrochloric solutions or in pure ject, the results of which appear to him to gastric juice, and is profoundly altered after show that the amylolytic ferment secreted by passing into the mixed gastric juice, so that if the salivary glands is destroyed by the hydro- it still dissolves starch it no longer saccharifies chloric acid of the gastric juice, that the pro- it. Ptyalin is recommended as an excellent teolytic and rennet ferments secreted by the re-agent for demonstrating the difference begastric glands are destroyed by the alkaline tween mixed gastric juice, which owes its acidsalts of the pancreatic and intestinal juices, ity to organic acids, and pure gastric juice, the and by trypsin, and that the proteolytic and strength of which is derived from hydrochloric amylolytic ferments secreted by the pancreas acid. are not improbably destroyed in the large in Seegen and Kratschner have brought a few testine by the acids formed there. In experi- new facts to light from their investigations of ments with ptyalin, it was found that a ptyalin the relations of sugar to glycogen in the liver ; containing fluid capable of converting a con- and while they find, in accordance with most siderable amount of starch into sugar in a few other observers, that the amount of sugar inminutes is incapable, after treatment at 35° C. creases after death, they maintain that this with hydrochloric acid of .04 per cent for seven increase does not take place, as is generally hours, of converting any appreciable amount accepted, at the expense of the glycogen, but of starch into sugar in three hours. As in all of some other substance; for not only does the the animals examined the fluid in the stomach quantity of sugar present augment, but a larger reddened litmus-paper very much more deeply percentage of glycogen can actually in some than does hydrochloric acid, the conclusion is instances be obtained some hours after the redrawn that the amylolytic ferment of the moral of the liver from the body than instantly saliva is destroyed at any rate by the end of after death. If this be true, and glycogen be gastric digestion; and it was corroborated by the result of a process of disintegration, some

other compounds must also be present in larger duction of these curves, but the contractions quantities shortly after death. If these can be they indicate are readily distinguished from discovered, and their composition ascertained, those which are proper to this organ and which it may hereafter be possible to trace the source are independent of changes in the blood-pressof the glycogenous and saccharine bodies by & ure. Stimulation either of the central end of process of synthesis.

a cut sensory nerve or of the medulla oblongata The lymphatics of the pancreas have been causes a rapid contraction of the spleen. Stimworked out and illustrated by Dr. and Mrs. ulation of the peripheral ends of both splanchHaggan. Sappey, of the Faculty of Medicine nics and of both vagi causes a rapid contraction. of Paris, has published a work on the morpho- After section of these four nerves, stimulation logical elements of the blood, in which he de- of a sensory nerve still causes a contraction, scribes the red and white corpuscles of each showing that vaso-constrictor influences may division of the animal kingdom, and has illus- pass from the cerebro-spinal centers to the trated them with many engravings. Crystal- spleen by some other route or routes than the lizable forms of albumen have been obtained nerves named. The fact that the section of from the seeds of the pumpkin and from hemp- these principal nerves which convey vasomotor seed, the latter presenting the octahedrio and influences from the cerebro-spinal centers to rhombic-dodecahedric forms that had been re- the spleen has so little effect on the rhythmic garded as peculiar to hæmoglobin.

contractions and expansions of the organ, seems Professor Charles S. Ray, M. D., has applied to indicate that the latter are regulated and to the investigation of the manner of action maintained by some mechanism contained in and the function of the spleen a method of indi- the spleen itself. rect observation in which he studied the rapid MÀ. H. Caillet de Poncy and C. Livron, or ity of the circulation through its blood-vessels. the Medical School at Marseilles, have found It is fully recognized by physiologists that, that, when poisoning by arsenic takes place, under normal conditions, à certain relation the phosphorus which exists as phosphoric acid subsists between the degree of functional ac in the brain is replaced by arsenic. The subtivity of an organ or tissue and the degree of stitution takes place in the lecithine, a very expansion of its blood-vessels. Applying this complex nitrogenized compound, which thus rule to a series of observations on the kidney, becomes transformed into an insoluble albumihe was surprised at the closeness of the corre- noid substance. Acute poisoning takes place spondence that existed between the activity too rapidly for the arseniated lecithine to be with which the renal circulation was carried subjected to physiological reactions and be elimon and the rapidity of the secretion of urine; inated, and the animal dies under the local which was so near that he found the rapidity influence of the poison without sensible variof the flow of urine could be observed indirectly ation of the normal phosphorus of the nervous by watching the changes in the caliber of the matter. In slow and chronic poisoning, the blood-vessels of the kidney with much greater replacement is less rapid; arseniated lecithine convenience than could be done directly by is formed and acts as ordinary lecithine, passcounting the number of drops of urine which ing gradually into the insoluble albuminoid escaped. It struck him that this method could state, while the phosphorus is steadily diminbe most usefully applied to the investigation of ished, giving place to the arsenic. organs whose functions can not be studied by Professor İ. P. Bow ditch and William F. any direct method with which we are as yet Southard, M. D., of the Harvard Medical School, acquainted, of which the spleen is a typical lave performed a course of experiments to asexample; and it is conveniently situated for certain which of the two senses, sight and the purpose. His observations taught him that touch, supplies us with the more accurate inthe circulation through the spleen differs from formation as to the position of objects around that of other organs in the important par us. The comparison muy be made in several ticular that the force which impels the blood ways, one of the most obvious of which is to through the organ is not that of the blood- compare the smallest distances within which pressure in the arteries, which has compara- two impressions made upon sensitive surfaces tively little influence on the volume of the can be recognized as separate and distinct. It spleen; but that the splenic circulation is car- has been found, for example, that the distance ried on chiefly, if not exclusively, by a rhtyh- between two luminous points, as two fixed mic contraction of the muscles contained in stars, must subtend a visual angle of at least the capsule and trabeculæ of the organ. The one minute, in order that the sources of light movement is exceedingly regular, in so far as may be recognized as separate and distinct from rhythm is concerned, and varied but slightly one another. This angle corresponds to a disduring hours of experiment and under consid- tance of 0.00438 millimetre on the retina. The erable changes of position. The process in the smallest distance upon the surface of the body spleen is different in nature from the rhythmic at which two tactile impressions are recognized contraction and expansion which may be ob- as distinct is, according to Weber's researches, served in various organs on the “Traube- 1.1 mm. (upon the tip of the tongue). Hence Hering” blood-pressure curves showing them- it should follow that the retina is 251 times selves. The spleen also takes part in the pro- more accurate than the most sensitive part of

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