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PERU, CHILI, AND UNITED STATES.

offenses avoided; that questions growing out of the suppression of the Calderon Government could be attended to at Washington; and that it was preferable that he should not visit Buenos Ayres on his way home. On the 9th of January, 1882, Secretary Frelinghuysen wrote to Señor Martinez, the Chilian Minister at Washington, acknowledging receipt of a note from the latter of December 28th, in which he gave his views as to the condition of Peru, derived from his latest intelligence. Secretary Frelinghuysen continues his letter as follows:

I was much gratified yesterday with the assurances which you gave me in our personal interview that your Government, in the arrest and imprisonment of Calderon, was in no way instigated by an unfriendly feeling toward the United States. If you feel yourself at liberty to renew that assurance in writing, I shall be still further and greatly obliged by your doing so. Such a communication, written in the friendly spirit which marked your verbal communications, will tend to promote that friendly feeling which is so desirable among American republics.

On the 10th of January Señor Martinez replied to this letter in a similar friendly spirit. On January 9, 1882, Secretary Frelinghuysen wrote to Mr. Trescot as follows:

SIR: Since you received your instructions on your departure as special envoy to Chili, Peru, and Bolivia, I have sent you by cable two instructions. As I have not heard of your having received them, and to make their purport more intelligible than the brevity of a telegram would permit, I send this, stating the proper construction of your original instructions, somewhat modifying them, and indicating how they are to be executed.

The President wishes in no manner to dictate or make any authoritative utterance to either Peru or Chili as to the merits of the controversy existing between those republics, as to what indemnity should be asked or given, as to a change of boundaries, or as to the personnel of the Government of Peru. The President recognizes Peru and Chili to be independent republics, to which he has no right or inclination to dictate. Were the United States to assume an attitude of dictation toward the South American republics, even for the purpose of preventing war, the greatest of evils, or to preserve the autonomy of nations, it must be prepared by army and navy to enforce its mandate, and, to this end, tax our people for the exclusive benefit of foreign nations. The President's policy with the South American republics and other foreign nations is that expressed in the immortal address of Washington, with which you are entirely familiar. What the President does seek to do is to extend the kindly offices of the United States impartially to both Peru and Chili, whose hostile attitude to each other he seriously laments; and he considers himself fortunate in having one so competent as yourself to bring the powers of reason and persuasion to bear in seeking the termination of the unhappy controversy; and you will consider as revoked that portion of your original instruction which directs you, on the contingency therein stated, as follows:

You will say to the Chilian Government that the President considers such a proceeding as an intentional and unwarranted offense, and that you will communicate such an avowal to the Government of the United States, with the assurance that it will be regarded by the Government as an act of such unfriendly import as to require the immediate suspension of all diplomatic intercourse. You will inform me immediately of the happening of such a contingency, and instructions will be sent to you."

Believing that a prolific cause of contention between two nations is an irritability which is too readily of

PHOTOGRAPHY, IMPROVEMENTS IN. 747

fended, the President prefers that he shall himself determine, after report has been made to him, whether President's wish that you do not visit (although inthere is or is not cause for offense. It is also the dicated in your original instruction that you should do so) as the envoy of this Government, the Atlantic republics after leaving Chili.

The United States is at peace with all the nations of the earth, and the President wishes hereafter to determine whether it will conduce to that general peace, which he would cherish and promote, for this Government to enter into negotiations and consultation for the promotion of peace with selected friendly nationalities without extending a like confidence to other peoples with whom the United States is on equally friendly terms. If such partial confidence would create jealousy and ill-will, peace, the object sought by consultation, would not be promoted. The principles controlling the relations of the republics of this hemisphere with other nationalities may, on investigation, be found to be so well established that little would be gained at this time by reopening a subject which is not novel. The President, at all events, prefers time for deliberation.

There is considerable correspondence relative to the Cochet and Landreau claims, but a want of space makes it necessary at present to pass it over.

PHOTOGRAPHY, IMPROVEMENTS IN. The collodion process of photography, which has been in use for thirty years, is being generally supplanted by the new dry process, in which gelatine is employed to hold in suspension the sensitive salts of silver. The preparation of the gelatino-bromide plates is conducted as follows: To a solution of fine gelatine in water is added bromide of potassium or bromide of ammonium. In another vessel nitrate of silver is dissolved in water. In a room lighted only through dark ruby glass the solution of silver salt is gradually stirred into the mixture of bromide and gelatine. When great sensitiveness is required, it is to be kept in a fluid condition for from one to four days. Ordinarily it is left only a few hours, and can be more rapidly evaporated by heating. The emulsion is next freed from the nitrate of potassium or ammonium by breaking it into pieces after it has been allowed to set in a deep dish, and washing it in several changes of cold water. It is then melted into plates, after being drained. After the plates have been coated and dried they are ready for use. These dry plates can be kept any length of time without losing Plates which are thus their sensitiveness. made in quantity and are always ready can be employed in out-of-door and amateur work, and for the many scientific uses of photography in which the troublesome wet process, requiring the use of chemicals and a dark chamber, would be difficult or impossible. The convenience of the gelatine and bromide process is not its only advantage. The images rendered are as clear and perfect as any obtained from collodion plates, and the impressions are formed in the camera in one sixth to one tenth the time of exposure. The action on the most highly sensitive gelatine plates is practically instantaneous, pictures having been taken in of a second.

PHYSIOLOGY, RECENT. Physiological science has made great advances under the system of specialized minute investigation of the different tissues and organs of the body and their functions which is now very generally applied. Nearly every vessel and nearly every fluid of the body has been subjected under this system to a most rigid and searching microscopic, chemical, and dynamic examination, and is thereby being made to disclose the most intimate secrets of its structure and function. Dr. Ferrier and Professor Yeo have added to the clearness of the evidence of the localization of function in the cortex of the brain from observations made in their experiments on monkeys. They are able, after having effected a localized or limited lesion by means of the galvanic cautery of the surface of the brain, to predict the precise phenomena of paralysis which will occur. On microscopical examination after death following these phenomena, strands of fibers proceeding from the damaged parts of the cortex may be traced down to the motor or sensory ganglia at the base of the brain, and thence downward through the spinal cord to the muscles paralyzed by the lesion. Exner, who has been engaged in considering localization in the function of the brain by the aid of the phenomena presented by pathological changes, has satisfied himself by that method of the existence of very limited areas on the surface of the brain, destined to receive impressions and original motor impulses. Couty's researches on the same point, published in Brown-Séquard's "Archives," appear to be altogether opposed to Ferrier and Hitzig's conclusions.

Professor Charles S. Ray, assisted by G. H. Lewes, student, and J. Graham Brown, M. D., has pursued an investigation of the blood-pressure and its variations in the arterioles, capillaries, and smaller veins. Attempts had been previously made to measure the pressure of the blood in the capillaries by N. V. Kries, whose experiments were made upon the vessels of the human skin, particularly on that part of the distal phalanx of one of the fingers inmediately behind the nail. The method he employed consisted in pressing, by means of weights, a small glass plate of known area upon the portion of skin selected, and finding the weight required to produce a distinct whitening of the compressed as compared with the surrounding skin. It was assumed, in making these experiments, that the pressure which sufficed to cause an evident change in the color of the small area of skin lying under the glass plate, was equal to the pressure of the blood in the capillaries lying nearest the surface. This method was applied with some satisfaction to the determination of the relative values of pressure under varied conditions. Professor Ray sought a more delicate method for the study of the absolute values of the pressure by means of microscopic examinations of the web of a frog's foot. The first observations showed that as

the pressure to which the portion of tissue examined was subjected was raised, the current of blood through the smaller arterioles lost the equable character which it normally presents, and a rhythmic variation in rapidity, a pulse which could not be detected in the small arteries while the tissue was uncompressed, each increase corresponding with a heart-beat, became more and more evident. The blood-flow through the capillaries also became more and more pulsatile in character, and, in that part of the capillary plexus which lies nearest the arteriole whence the blood came, a temporary arrest of circulation took place when a certain pressure, which was different at different points, was reached. It was also found that the capillaries which first cease to convey blood under these circumstances are not always the same, a fact which can not be easily explained otherwise than by assuming that the relative diameters of the capillaries have changedthat some vessels have expanded while others have contracted-in the interval between two observations. In favorable instances such a change in the diameter of the different vessels can be verified with the help of a micrometer. The small veins, or venous rootlets, show under the application of pressure a diminution of diameter, often to one third of the original caliber, accompanied with an increase in the flow of blood through their interior. The flow of blood in the veins becomes accelerated with each pulse-wave in the arterioles, and slowed between the beats; and when the blood no longer advances in the arteriole, the corresponding vein or veins become empty or collapsed. It has long been known that capillary vessels may present considerable variations in diameter at different times, and these variations have been ascribed to the elasticity of the capillary walls. Professor Ray's experiments, however, tend to show that modifications of the intra-capillary pressure, much greater than those which can normally occur, influence but slightly the caliber of the capillaries, and lead almost inevitably to the conclusion that the capillaries are contractile as well as elastic. To the question whether this contractility resides in some anatomically differentiated part of the capillary wall, or whether it be a property inherent in the wall as a whole, the answer may be returned that capillary vessels may be seen to vary greatly in diameter without any localized contraction or expansion being visible; that the capillary tube expands or contracts as a whole, its diameter remaining equal throughout its whole length. The anæmia or absence of blood which is produced on any part by pressure is followed, when the pressure is removed, by an excess of blood or congestion, which gradually passes away. This phenomenon has been proved not to reside in any reflex action through the cerebro-spinal vasomotor centers; hence attention is directed to the probability of some peripheral vasomotor mechanism by which the degree of dilata

tion of the vessels of the skin is capable of being regulated independently of the cerebro-spinal vasomotor centers. It is not clear what is the nature of this mechanism, but it seems to be adequate to measure out the degree of dilatation according to the requirements of the tissues, and appears to be the same that is called into action under the application of irritants. The capillary vessels have been shown to be capable of varying their diameters independently of one another. The conclusion is logically derivable that each capillary is capable of varying its caliber in accordance with the requirements of the tissues which it supplies with blood. To this automatic regulation of the peripheral circulation Professor Ray is inclined to ascribe & function of great importance, both from a physiological and a pathological point of view; and it appears that it is principally, if not exclusively, in connection with it that the contractility of the capillaries comes into play.

Dr. J. N. Langley, of Trinity College, Cambridge, has brought the subject of the histology of the gastric or pepsin-making glands before the Royal Society, in a paper in which he has sought to collate the proofs, from his experiments, that the gastric glands in life contain no ferment, but much zymogen or substance capable of giving rise to ferment; that by far the greater part of the zymogen can be seen in the chief cells in the form of granules; and that during digestion the granules are usually used up in such a manner as to give rise to an outer non-granular and an inner granular zone in the chief cells. These points, if proved, would establish fundamental resemblances in life-habit between the chief cells of the gastric glands of mammals, the cells of the gastric glands of the lower vertebrates, and the cells of the pancreatic gland. It was found that the chief-cell granules of some mainmals are preserved by osmic acid, while those of others are not. The examinations were made chiefly with preparations of the former class, and were checked by comparison with glands in the fresh state; they related to the border cells and the chief cells of different regions of the stomach. In both the mouse and the mole, in the hungry state, the chief cells are granular throughout; in the digestive state, the chief cells have an outer non-granular zone of from one third to one half of the cell. In the Guinea-pig and the rabbit the chief cells of the latter part of the greater curvature show few or no granules; in the median part of the greater curvature the glands have usually an outer clear zone, which diminishes in passing toward the fundus, while in the fundus and in the adjoining part of the greater curvature the chief cells are granular throughout. During digestion an outer clear zone is formed in the glands of the latter part of the fundus and the fore part of the greater curvature, while the cells of the rest of the greater curvature lose more or less completely their granules. Heidenhain first announced

the conclusion that the chief and not the border cells produce pepsin. This is confirmed by Dr. Langley's comparison of the pepsin contents of the different stomach regions in several animals. In each case the amount of pepsin found bore no relation to the number of border cells, but almost always varied directly with the number of chief cells. It was also shown that in the different regions of the stomach of the rabbit most pepsin is found where the granules are most numerous. It is now very generally accepted that pepsin exists in the gastric glands partly free and partly combined-i. e., partly as pepsin and partly as pepsinogen. A series of experiments made with especial reference to this point has convinced Dr. Langley that pepsin, as such, does not exist in the living glands, but that in the animals with which he worked, and probably in all vertebrates, the gastric glands store up pepsinogen and not pepsin. This is converted by hydrochloric acid into pepsin. As far as our knowledge goes, rennet - ferment is found in greatest quantity where there is most pepsin, and both vary pari passu. Perhaps, suggests Dr. Langley, the granules of the chief cells may contain zymogen both of pepsin and of rennet-ferment, and he offers this as a subject for further observation. In all the vertebrates in which the gastric glands have been carefully examined in the living state, it has been found that those gastric glands which produce most ferment store up their zymogen in the form of granules. The ferment-forming cells consist of a net-work of protoplasm, inclosing a mass of granules. It seems probable, on general grounds, that the cells should store up other antecedent substances besides zymogen, and we are not without facts which will tell in favor of this view. In the saliva of many animals ferment is almost or entirely absent, but mucin and proteids occur. We have some proof that mucin arises during secretion from the splitting up of an antecedent substance, mucigen, which is stored up in the cell; in the serous salivary glands, and in the lachrymal glands, the occurrence of granules which are used up during secretion, just as are the granules of the pancreas or of the gastric glands, makes it extremely probable that in those glands some antecedents of the proteids found in the secretion, not the actual proteids of the secretion, are stored up. Apparently, then, a large number of gland-cells have the feature in common that the cell protoplasm forms certain antecedent substances, which Dr. Langley proposes shall be called "mesostates," which it stores up, and that are converted, when secretion takes place, into secretory products. In the pancreas the chief mesostate is trypsinogen, in the gastric glands it is pepsinogen, in the mucous glands it is mucigen, etc.

Observations made by Uffelmann on a patient upon whom gastrotomy had been performed, have indicated that no hydrochloric acid is secreted during the earlier stages of

digestion, although that substance may sometimes be found in the course of three quarters of an hour or an hour after the ingestion of food. The acid present was always lactic, even when the conversion of albumen into peptone, and of starch into dextrine and sugar, was distinctly taking place. The observations of Cash, made in Ludwig's laboratory, have shown that, contrary to the statements usually given in text-books, fats may be split up in the stomach into the fatty acids and glycerine, while an acid, perhaps the lactic, is formed. It is a remarkable fact that although after the full digestion of every meal a considerable quantity of peptones must be introduced into the blood, none passes off by the kidneys; yet if solutions of the peptones be directly injected into the blood-vessels, from 60 to 70 per cent is rapidly eliminated by these organs. Hofmeister, finding peptone abundant in the wall of the intestine, has arrived at the conclusion, from his experiments on this point, that the numerous nuclei and cells which occupy the meshes of the adenoid tissue of the intestinal mucous membrane fix the peptones, and thus enable them to enter the bloodcurrent without the danger of being excreted by the kidneys. The white corpuscles, on this view, act as carriers of nutritive material to all parts of the body, just as the red corpuscles act as carriers of oxygen.

During digestion much saliva, gastric juice, and pancreatic juice flow into the alimentary canal, each secretion bearing with it a considerable quantity of ferment, chiefly either amylolytic or proteolytic. Very little, how ever, is known of the fate of these ferments; for the little of them that may be found in the fæces and urine makes but a small fraction of the whole amount which is received by the alimentary canal during digestion. Dr. J. M. Langley has made investigations on this subject, the results of which appear to him to show that the amylolytic ferment secreted by the salivary glands is destroyed by the hydrochloric acid of the gastric juice, that the proteolytic and rennet ferments secreted by the gastric glands are destroyed by the alkaline salts of the pancreatic and intestinal juices, and by trypsin, and that the proteolytic and amylolytic ferments secreted by the pancreas are not improbably destroyed in the large intestine by the acids formed there. In experiments with ptyalin, it was found that a ptyalin containing fluid capable of converting a considerable amount of starch into sugar in a few minutes is incapable, after treatment at 35° C. with hydrochloric acid of '04 per cent for seven hours, of converting any appreciable amount of starch into sugar in three hours. As in all the animals examined the fluid in the stomach reddened litmus-paper very much more deeply than does hydrochloric acid, the conclusion is drawn that the amylolytic ferment of the saliva is destroyed at any rate by the end of gastric digestion; and it was corroborated by

an experiment in which the diluted parotid extract retained but a trace of its amylolytic power when it was warmed for fifteen minutes with one tenth of its bulk of gastric fluid. The destructive action of even very dilute acids was found to be extraordinarily rapid. The secretions from the pancreas and intestinal glands are also capable of dissolving the gastric ferments, and owe their power chiefly to their alkaline salts. The action of these salts, as exemplified in sodium carbonate, is decided and rapid. It is augmented when trypsin is also present, but the effect of trypsin alone is less marked. The rennet ferment is, like pepsin, destroyed rapidly at the body temperature by sodium carbonate, and to some extent by trypsin; whence we may conclude that it also loses its ferment power irrecoverably in the small intestine. Since trypsin is destroyed both by hydrochloric acid and by pepsin, the administration of pancreatic extract with food in medical practice to aid digestion is of more than doubtful benefit; for little, if any, trypsin can pass into the duodenum to exercise a digestive function there. An extract of the pancreas rapidly loses its amylolytic power when warmed with dilute hydrochloric acid, more rapidly than does trypsin under similar circumstances, but apparently less rapidly than does the amylolytic ferment of the parotid.

Recent researches reported by M. Dufresne throw new light on the relations of ptyalin, diastase, and the gastric juice. It has been a subject of debate whether the saliva is destroyed in the gastric juice, or continues in the stomach its action on starch. M. Dufresne's experiments prove that the saliva is paralyzed in pure gastric juice, but recovers its action in the mixed gastric juice and in the duodenum, and is capable of continuing the process of saccha rification; while diastase is irrecoverably destroyed in hydrochloric solutions or in pure gastric juice, and is profoundly altered after passing into the mixed gastric juice, so that if it still dissolves starch it no longer saccharifies it. Ptyalin is recommended as an excellent re-agent for demonstrating the difference between mixed gastric juice, which owes its acidity to organic acids, and pure gastric juice, the strength of which is derived from hydrochloric acid.

Seegen and Kratschner have brought a few new facts to light from their investigations of the relations of sugar to glycogen in the liver; and while they find, in accordance with most other observers, that the amount of sugar increases after death, they maintain that this increase does not take place, as is generally accepted, at the expense of the glycogen, but of some other substance; for not only does the quantity of sugar present augment, but a larger percentage of glycogen can actually in some instances be obtained some hours after the removal of the liver from the body than instantly after death. If this be true, and glycogen be the result of a process of disintegration, some

other compounds must also be present in larger quantities shortly after death. If these can be discovered, and their composition ascertained, it may hereafter be possible to trace the source of the glycogenous and saccharine bodies by a process of synthesis.

The lymphatics of the pancreas have been worked out and illustrated by Dr. and Mrs. Haggan. Sappey, of the Faculty of Medicine of Paris, has published a work on the morphological elements of the blood, in which he describes the red and white corpuscles of each division of the animal kingdom, and has illustrated them with many engravings. Crystallizable forms of albumen have been obtained from the seeds of the pumpkin and from hempseed, the latter presenting the octahedric and rhombic-dodecahedric forms that had been regarded as peculiar to hæmoglobin.

duction of these curves, but the contractions they indicate are readily distinguished from those which are proper to this organ and which are independent of changes in the blood-pressure. Stimulation either of the central end of a cut sensory nerve or of the medulla oblongata causes a rapid contraction of the spleen. Stimulation of the peripheral ends of both splanchnics and of both vagi causes a rapid contraction. After section of these four nerves, stimulation of a sensory nerve still causes a contraction, showing that vaso-constrictor influences may pass from the cerebro-spinal centers to the spleen by some other route or routes than the nerves named. The fact that the section of these principal nerves which convey vasomotor influences from the cerebro-spinal centers to the spleen has so little effect on the rhythmic contractions and expansions of the organ, seems to indicate that the latter are regulated and maintained by some mechanism contained in the spleen itself.

Professor Charles S. Ray, M. D., has applied to the investigation of the manner of action and the function of the spleen a method of indirect observation in which he studied the rapid- MM. 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, a 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 any direct method with which we are as yet acquainted, of which the spleen is a typical example; and it is conveniently situated for the purpose. His observations taught him that the circulation through the spleen differs from that of other organs in the important particular that the force which impels the blood through the organ is not that of the bloodpressure in the arteries, which has comparatively little influence on the volume of the spleen; but that the splenic circulation is carried on chiefly, if not exclusively, by a rhtyhmic contraction of the muscles contained in the capsule and trabeculæ of the organ. The movement is exceedingly regular, in so far as rhythm is concerned, and varied but slightly during hours of experiment and under considerable changes of position. The process in the spleen is different in nature from the rhythmic contraction and expansion which may be observed in various organs on the "TraubeHering" blood-pressure curves showing themselves. The spleen also takes part in the pro

Professor H. P. Bowditch and William F. Southard, M. D., of the Harvard Medical School, have performed a course of experiments to ascertain which of the two senses, sight and touch, supplies us with the more accurate information as to the position of objects around

us.

The comparison may be made in several ways, one of the most obvious of which is to compare the smallest distances within which two impressions made upon sensitive surfaces can be recognized as separate and distinct. It has been found, for example, that the distance between two luminous points, as two fixed stars, must subtend a visual angle of at least one minute, in order that the sources of light may be recognized as separate and distinct from one another. This angle corresponds to a distance of 0·00438 millimetre on the retina. The smallest distance upon the surface of the body at which two tactile impressions are recognized as distinct is, according to Weber's researches, 11 mm. (upon the tip of the tongue). Hence it should follow that the retina is 251 times more accurate than the most sensitive part of

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