Page:Encyclopædia Britannica, Ninth Edition, v. 15.djvu/360

338 M A L - M A L period, but his services were secured for his native uni versity, and he spent the next twenty-five years there. In 1691, being then in his sixty-fourth year, and in failing health, he removed to Rome to become private physician to Pope Innocent XIL, and he died there of apoplexy three years later. In the portrait prefixed to his autobiography, the features are those of the phlegmatic type. His addiction to the microscope brought him into conflict with the re spectabilities of the medical profession, including two of his colleagues at Bologna, whose names have been pre served from oblivion ; it was felt by those who affected to watch over the future welfare of medicine that the study of microscopic anatomy was adverse to the true interests of medical practice, and that feeling is said to have found expression in a duel that was fought between the brother of Malpighi and a near relative of one of his con servative colleagues, in which the latter combatant was killed. Amid such incidents was the fruitful microscopic era of medical and biological science ushered in. The compound microscope (invented in the Netherlands) had been used in Italy (Rome) to study the parts and organs of the bee as early as 1625, and it was employed by Malpighi and by his con temporaries Hooke (botanist) and Leeuvvenhoek ; the illumination of the objects was always direct, the mirror being a much later addition, and the tube was of unwieldy length. Owing to the inability to overcome spherical and chromatic aberration in com pound lenses, the simple microscope came again into common use, and continued to be the chief instrument in the study of minute anatomy until the introduction of flint-and-crown glass lenses by English opticians about a century later. It was Malpighi s prac tice to open animals alive, and some of his most striking discoveries were made under those circumstances. Althoxigh Harvey had correctly inferred the existence of the capillary cir culation, he had never seen it ; it was reserved for Malpighi in 1661 (four years after Harvey s death) to see for the first time the marvellous spectacle of the blood coursing through a network of small tubes on the surface of the lung and of the distended urinary bladder of the frog. ~Ye are enabled to measure the diffi culties of microscopic observation at the time by the fact that it took Malpighi four years longer to reach a clear understanding of the corpuscles in the frog s blood, although they are the parts of the blood by which its movement in the capillaries is made visible. His discovery of the capillary circulation was given to the world in the form of two letters De Pulmonibus, addressed to Borelli, published at Bologna in 1661 and reprinted at Leyden and other places in the years following ; the letters to Borelli contained also the first account of the vesicular structure of the human lung, and they made a theory of respiration for the first time possible. The achievement that comes next both in import ance and in order of time was a demonstration of the plan of struc ture of secreting glands ; against the current opinion (revived by Ruysch forty years later) that the glandular structure was essentially that of a closed vascular coil from which the secretion exuded, he maintained that the secretion was formed in terminal acini standing in open communication with the ducts. The name of Malpighi is still associated with his discovery of the soft or mucous character of the lower stratum of the epidermis, of the vascular coils in the cortex of the kidney, and of the follicular bodies in the spleen. He was the first to attempt the finer anatomy of the brain, and his descriptions of the distribution of grey matter and of the fibre-tracts in the cord, with their extensions to the cerebrum and cerebellum, are distinguished by accuracy ; but his microscopic study of the grey matter conducted him to the opinion that it was of glandular structure and that it secreted the "vital spirits." At an early period he applied himself to vegetable histology as an introduction to the more difficult study of the animal tissues, and he was acquainted with the spiral vessels of plants in 1662. It was not till 1671 that he wrote his Anatome Plantarum and sent it to the Koyal Society, who published it in the following year. An English work under a similar title (Anatomy of Vegetables) had been pub lished in London a few months earlier, by Nehemiah Grew ; so that Malpighi s priority as a vegetable histologist is not so incon testable as it is in animal histology. The Anatome Plantarum contained an appendix, Observations de ovo incubato, which gave an account (with good plates) of the development of the chick (especially of the later stages) in many points more complete than that of Harvey, although the observations were needlessly lessened in value by being joined to the metaphysical notion of " praedelinea- tion" in the undeveloped ovum. His works are De pulmonibus : Epistolas duas ad Borellium, Bologna, 1661 (went through several editions) ; Epistolas anatomies^ Marc. Malpighii et Car. Fracassati, Amsterdam, 1662 (on the tongue, brain, skin, omentum, &c. ) ; DC Viscerum Structura : excrcitatio anatomica, London, 1669; Anatome Plantarum, cum appendice observationcs de ovo incubato contiriente, London, 1672 (other editions .in 1675 and 1679); De Structura Glandularum conglobatarum, London, 1689; Opera posthuma, et vita a seipso scripta, London, 1697 (another edition, with preface and additions, was published at Amsterdam in 1700). An edition con taining all his works except the last two was published in London in 1687, in 2 vols. folio, with portrait and plates. MALSTATT-BURBACH, a town in the district of Treves, Prussia, is situated on the right bank of the Saar (Sarre), almost contiguous with the town of St Johann, and separated from Saarbriicken by the river. It lies in the midst of an important coal-mining and industrial district, and is itself little more than a long and narrow row of manufactories and workmen s houses. The largest factories are engaged in the production of iron, steel, and cement, one iron-work employing nearly 2000 men, and producing 285,000 tons of raw and manufactured metal annually. There is a large wharf on the river for the export of coal. At the census of 1880 Malstatt-Burbach contained 13,158 inhabitants. Malstatt is of very ancient origin, and received municipal rights in 1321. These, however, were afterwards resigned to the newer town of Saarbriicken, and in 1818 Malstatt and Burbach were two small villages with a joint population of only 822. About the- middle of the century the population began to increase rapidly, in consequence of the development of the mining industry of the district and the extension of the railway system, and in 1875 the two villages vere united to form a town. In 1870 Malstatt- Burbach was cannonaded by French troops under the command of Napoleon III. MALT is the grain of any cereal artificially germinated so as to induce certain changes in the constitution of the seed, specially a conversion of a portion of the starch into sugar. The varieties of grain usually employed for malting are barley and bere or bigg, and the processes of preparing the substance are fully explained under BREWING (vol. iv, p. 2GG). The specific effect of the malting of grain is to transform by the process of germination a proportion of the starch into soluble sugar and dextrin. These changes are effected by the agency of a peculiar nitrogenous ferment, diastase, which exists in the grain, but which is increased in amount during the germination. The precise sequence of changes, and the exact nature of the new chemical compounds evolved, are still matters of some doubt. It is clearly established that the ferment of barley is in capable of transforming the starch on which it operates entirely into sugar, the ultimate products of the action being partly dextrin and partly sugar. The relative proportions of these bodies evolved by fermentation from starch have been matter of dispute, some holding that from three molecules of starch there are evolved two molecules of dextrin and one of sugar, while others affirm that the yield is two of sugar and one of dextrin, and a third party hold that for each molecule of sugar there is one of dextrin produced, thus : Starch. Sugar. Dextrin. 2C 6 H 10 5 + H,0 - C 6 H 12 6 + C 6 H 10 5 . These statements, however, are based on the assumption that the sugar which results from the fermentation of germinating barley is ordinary grape sugar or dextrose, C 6 H 12 6 ; but it has been demonstrated, first by O Sullivan, that it is a form of sugar possessed of peculiar properties to which the name maltose has been given. Maltose, according to O Sullivan, is isomeric with cane sugar, C 12 H 22 O n , but Marcker considers that its constitution should be represented by C 18 H 34 17 , and that the equa tion is as follows : Starch. Maltose. Dextrin. 4C 6 H W 5 + 2H 2 = C 18 H 34 17 + C 6 H 10 6 .

Maltose possesses the power of reducing Fehling s solution