Page:The New International Encyclopædia 1st ed. v. 01.djvu/548

AMICUS CURIÆ. which the judge is doubtful, or information upon matters of fact of which the court may take judicial cognizance. The amicus curiæ cannot add anything to the record or increase the power of the court to dispose of the matter in hand. The amicus curiæ in general has no control over an action, as does the attorney of record; but in some cases, as when letters of administration have been issued without authority, he may move to set the proceeding aside. By an early English statute the amicus curiæ was permitted to move to quash an improper indictment.

AM'IDAS, Philip. See.

AM'IDAVAD' (amadavat, Indian name; the bird was first imported from the city of Ahmedabad). A cage-bird (Estrilda amandara), one of the small weaver-finches of India, having a pretty song and a social disposition, so that it is a favorite for aviaries. The plumage is most brilliant, the prevailing colors being fiery red, black, and yellow. It requires the food and care given to a canary. See.

AM'IDES, or ACID AM'IDES (derived from ammonia). An interesting class of organic compounds formed by the substitution of organic acid radicles for one or more hydrogen atoms in ammonia (NH3). If one of the hydrogen atoms of ammonia is replaced by an acid radicle, the resulting compound is termed a primary amide; if two acid radicles are introduced into the molecule of ammonia, a secondary amide is obtained; finally, if all the three hydrogen atoms of ammonia are replaced by acid radicles, a ter- tiary amide is obtained. The relation of these three sub-classes of amides to ammonia is shown by the following formulæ, representing com- pounds containing one or more acetyl groups (radicles of acetic acid):

/H /COCH /COCH3 /COCH, N_H N— H N-COCH3 N— COCH, H H H COCH, Ammonia Acetamide Di-acetylamide Tri-acftylamide (a primary (a secondary (a tertiary amide) amide) amide)

Amides are also subdivided into fatty and aromatic amides, according as their acid radicles are derived from fatty or from aromatic acids; thus, acetamide (corresponding to acetic acid) is a fatty amide, while benzamide (derived from benzoic acid) is an aromatic amide.

The primary amides are by far more numerous and important than the secondary or tertiary amides. From the above it is evident that their molecule consists of two parts: viz., one acid radicle and the group NH.. A number of inter- esting derivatives of the amides have been ob- tained by replacing the hydrogen of the latter group. Thus, from acetamide, CH,.,CONH,, com- pounds may bo readilv obtained, represented by the following formuhe: CH.CONH (CH,)— me- thvl-acetamide; ClLCONfCHj),— di-methyl-acet- amide; CHX'ONHAg— silver-acetamide; CH.CO KHBr — bromine-acetaniide, etc.

The following are the principal general methods by which primary acid amides may be prepared:

1. When the ammonium salts of many fatty organic acids are distilled, they lose the elements of water, and the corresponding amides are formed. Thus, acetamide is made by distilling

ammonium acetate, the reaction taking place according to the following chemical equation:

CH3COONH, — H,0 = CH3CONH, Ammonium acetate Acetamide

2. The chlorides of acid radicles are treated with ammonia. Thus, benzamide (the amide of benzoic acid) is readily prepared by slowly adding benzoyl chloride to strong ammonia in the cold, the reaction taking place as follows:

CoH^COCl + NH3 = C„H,CONH, + HCl Benzoyl Anmionia Benzamide Hydro- clUoride chloric acid

When acid amides are boiled with dilute acids or alkalies, they take up the elements of water and are reconverted into the ammonium salts of the corresponding acids. Thus, acetamide yields ammonium acetate, according to the following equation:

CH3CONH, + H,0 = CH3COONH. Acetamide Ammonium acetate

The amides are all soluble in alcohol and in ether, and many are more or less soluble in water. Most of them are solid crystalline substances that can be distilled without decomposition.

The acid amides should be distinguished from the amido-acids: compounds of the latter class may be obtained by treating the halogen-substitution products of acids with ammonia, while, as stated above, the acid amides are produced by the action of ammonia on the chlorides of acid radicles. The following two equations may serve to show the formation of, and the difference in chemical constitution between, an acid amide and an amido-acid:

CH3CONH2 + HCl Acetamide CH3COCI -I- NH3 Acetyl chloride /CI X-NH, CH.COOH -f NH3 = CH,CdOH + HCl Mono-cliloro- Amido-acetic acid acetic acid

AM'IDO -ACIDS. See.

AMID'SHIP, or See.

AMIEL, a'myel', Henri Frédéric (1821-81). A Swiss essayist, poet, and professor of æsthetics. He was born at Geneva, September 27, 1821, and died there, May 11, 1881. He is remembered almost solely for his Journal intime, a diary of 1700 pages of manuscript, posthumously published in part in 1883-84 and translated into English in 1889, with a critical study by Mrs. Humphry Ward. This journal, through its singular clearness, keenness; of insight, and sensitiveness to impression, is the complete revelation of a cast of mind that felt itself peculiarly modern and peculiarly entitled to be self-distressed. It expresses with masterful passion and original power the spiritual yearning and despair of a pure soul gasping in a rationalistic atmosphere. Thus Amiel is a curious projection into reality of the Shakespearean Hamlet, in whom morbid introspection numbs action. He is more fascinating than stimulating, more sombre than pessimistic, more subtle than strong. His thoughts will be cherished for the beauty of their form rather than for any tonic quality in their teaching. There is a Life of Amiel, by Vadier (Paris,