Cocaine is another alkaloid which was discovered as the result of the use by natives of S. America of the leaves of the coca plant as a stimulant. The active ingredient of these leaves is the alkaloid cocaine, which was found to be a powerful local anaesthetic and which rapidly displaced from use the older and less efficient remedies for the prevention of local pain. But the stimulant action of cocaine on the brain has not been overlooked by civilized races; and the habit, insidious and disastrous, of indulging in cocaine as a stimulant has become a serious problem especially in America and in France and has necessitated restrictive legislation upon the sale of the drug in most countries. This is only one of the many drugs used as a stimulant-intoxicant, others being morphine and its derivatives and the various hypnotics. When drugs having this narcotic action are taken for a very few times the person rapidly develops a craving for them. If the practice is continued, larger and larger doses have to be taken to produce the same effect, and in no long period a habit is developed, always difficult and sometimes impossible to break off.
One disadvantage of cocaine as a local anaesthetic for example in dentistry is that it is a very poisonous substance if absorbed into the general bloodstream in sufficient quantity and with sufficient rapidity. This danger can be prevented to a large extent, as is now the general practice, by injecting with it adrenaline which causes such a powerful contraction of the blood-vessels in the region of the injection that the cocaine is absorbed very slowly ; and, as it is being excreted continuously, the risk of a dangerously high concentration occurring in the blood is minimised. Artificial compounds resembling cocaine have been manufactured which are equally good local anaesthetics but are less generally poisonous. Such local anaesthetics act by blocking the passage of impulses through the nerves, so that painful sensations can no longer pass through the affected nerve. A similar effect can be produced on the spinal cord if the anaesthetic is injected so as to come into immediate contact with it. By this method of " intra-spinal anaesthesia " the whole of the lower limbs and of the lower part of the body can be rendered insensitive to pain, because conduction of pain sensations from this region to the receiving station (the brain) is blocked at the site of injection.
The plant belladonna is said to have been so named because it was used in by-gone days by ladies fair for the sinister purpose of dilating their pupils to enhance their charms. The chief active principle of belladonna atropine is still in daily use for dilating the pupil, usually under more prosaic circumstances. This effect is only one example of a general action of atropine in paralysing all parasym- pathetic nerve terminations throughout the body. Other closely allied alkaloids found in other plants of the order Alropaceae have a similar action. One such alkaloid, hyoscine, also called scopolamine, differs from atropine in its action on the central nervous system, having a depressant in place of a stimulant action, and hyoscine is now in common use as a hypnotic for certain conditions. In com- bination with morphine, it is used to produce general analgesia, with temporary loss of memory, in the treatment of child-birth, for which the romantic name of " twilight sleep " has come into vogue.
Hyoscine contains an asymmetric carbon atom and laevo-rotatory hyoscine is much more active than the dextro-rotatory form. This difference ^a superior activity of the laevo-com pound has been found also in the case of other optical isomers, e.g. of adrenaline and hyoscyamine, and seems to be very generally true.
Ipecacuanha has been used as a remedy for dysentery with varying success for nearly three centuries. It is now known for certain that it is curative only in one form of dysentery, that due to an amoeboid parasite; and also that the curative effect is due to the fact that the alkaloid emetine found in ipecacuanha is, though possibly only indirectly, a specific poison for this parasite. Emetine is now given hypodermically in amoeboid dysentery and an artificial compound of it emetine bismuth iodide has been found superior to it in the treatment of chronic dysentery.
Consequent upon the advances in knowledge of the physiology and pathology of the heart, the cardiac tonics of which digitalis is the chief have been investigated more fully, and a considerable part of the advantageous action of digitalis in heart disease, especially in auricular fibrillation, is found to be due to its impairing the con- duction from the auricle to the ventricle.
Drugs which cause the muscle of the uterus to contract are of great value in certain cases of labour, especially for preventing uterine haemorrhage. The extract of pituitary gland, which powerfully stimulates the contractions of the uterus, has now largely replaced the preparations of ergot so long used in midwifery practice for this purpose. The active principles of ergot itself have at last been determined and two of them found to be amines tyramine and histamine derivatives of the aminoacids tyrosine and histidine respectively. The discovery of the wide incidence of such amines, of their physiological action and of their chemical relation to adrenaline, has formed one of the most brilliant and fruitful chapters in modern biological research and has tended to bring into closer relation and cooperation the subjects of physiology, pharmacology and pathology. (J. A. G.*)
PHILADELPHIA (see 21.367), retaining its rank as third city in the United States, had in 1920 a pop. of 1,823,779, an in-
crease of 274,681 or 17-7% over the 1,549,098 of 1910. The pop. of 1920 comprised whites, 1,688,313; negroes, 134,098, and
Chinese, Japanese and Indians, 1,368. The increase in the white
pop. since 1910 was 224,942 or 15-4%, while the correspond-
ing increase in the negro pop. was 49,639 or 58-8%. In 1920
males were 908,067, or 49-8%, and females 915,712, or 50-2%.
Government and Finance. The Bullitt Act, under which the city government had functioned since 1887, gave way in 1920 to the Woodward Act, which became effective with the beginning of the term of Mayor J. Hampton Moore, in Jan. 1920. The new charter differs greatly from its predecessor. Under it a dual coun- cil is succeeded by a single body composed of one member for each 20,000 assessed voters in each state senatorial district, the mem- bership in 1920 being twenty-one. The councilmen serve for four years, and receive a salary of $5,000. In the executive de- partment, the department of supplies is superseded by a purchas- ing agent, and the department of health and public charities is separated into two with a director for each, the title " Public Charities " giving way to " Public Welfare." Further provisions enable the city to do its own street cleaning and garbage and ash removal, and place the great majority of city employees under civil service rules. By this provision not only small office-holders but the police and fire departments are removed from the possi- bilities of political activity.
The cost of city operations has grown steadily since 1911, when, under provisions of the state school code of May 18 1911, the Board of Education was separated from the city government. The com- bined cost in 1911 was $33,846,875.91. With the school expenses eliminated the cost in 1912 of city government was $30,2 13,067. 44; and, barring a slight decrease in 1913, has grown steadily until it reached $48,520,872.92 in 1919. The tax rate, with the school tax transferred to a separate item, was $1 in 1912, $1.25 in 1917, $1.75 in 1918 and $2.15 in 1920. This rate applied to real estate valued in 1919 at $1,805,494,000. At the close of 1919, the gross funded out- standing debt of the city was $173,473,450, of which the commis- sioners of the sinking fund held $31,898400, leaving a net funded debt outstanding of $141,575,050.
Commerce and Industry. As a distinctive manufacturing centre, Philadelphia shared the general depression of 1914, but advanced rapidly with the increasing European demand after the outbreak of the World War.
This is shown in the following table of the export values of the port of Philadelphia from 1910-20:
Ex|x>rts
Exports
1910 1911 1912
1913 1914
1915
$65,256,949 70,869,648 72,769,617 72,236,967 66,256,811 132,437.556
1916 1917 1918 1919 1920
$321,044,815 501,234,069 427,244,212 522,391,091 451,043,216
Importation figures also show a remarkable increase in the decade- The imports in 1910 were valued at $89,610,401; in 1915, $69,473. 983; and in 1920, $282,157,831. In 1910, 9,871,667 gross tons of shipping arrived and 9,771,266 tons cleared; in 1915, 9,315,157 tons arrived and 9,377,901 cleared ; and in 1920, 12,246,427 tons arrived and 12,820,377 cleared. The following table of coal exportation shows the increasing value of the product as compared with tonnage shipped :
Coal exported
in tons
Value
1910
1915 1919
866,148 1,127,415 1,072,773
$2,505,745 3,445,643 6,434,581
This remarkable increase in the activities of the port was made possible by the completion of large parts of the 35-ft^ channel from Allegheny Ave., Philadelphia, to the sea. The channel, about 800 ft. wide throughout, was 56 % completed on Dec. 31 1920 (the remain- ing sections having a depth of 30 ft.), while a similar channel in the Schuylkill river, from Passyunk Ave. Bridge to the Delaware, was 65 % completed. Both channels are national operations, authorized by Congressional action and carried on with biennial appropria- tions. The completion of more than half of the main channel opened the port to shipping of a heavier tonnage and the result was manifest in the increased number of lines plying from Philadelphia. In 1914 there were 27 transatlantic and 5 coastal lines; in 1918, at the close of the World War, 36 transatlantic and 4 coastal ; and in April 1 92 1 , 49 transatlantic and 10 coastal lines. A survey of the Pennsylvania department of internal affairs shows that Philadelphia in 1919 had 4,454 manufacturing establishments, with 297,436 employees, and products of $ 1 ,95 1 ,998,000. The capital invested was $ 1 ,005,658,500. Metals and metal products were first with 946 establishments, 66,991 employees, and products of $366,780,000. Textile factories
