- Harvest mites. (Larvæ of Trombidium)
- Dermanyssus gallinæ, female
- Dipylidium caninum. Rostrum evaginated and invaginated
- Dipylidium caninum. The double pored tapeworm of the dog
- Dog flea
- Some early medical entomology
- Sting of a honey bee
- The cattle tick (Boophilus annulatus). (a) Female; (b) male
- The Italian tarantula
- The yellow fever mosquito (Aëdes calopus)
- Two common centipedes
- Xenopsylla cheopis, male
- Head and pronotum of (a) dog flea; (b) of cat flea; (c) of hen flea (d) Nycteridiphilus (Ischnopsyllus) hexactenus
- Head of a spider showing poison gland (c) and its relation to the chelicera (a)
- Ixodes ricinus; male, ventral aspect
- Larva of Anopheles
- Larva of Fannia scalaris
- Larva of Simulium
- Left hand stigmata of the larvæ of muscoidea
- Left spiracle of nymph of Argas persicus
- Life cycle of the malarial parasite
- Linguatula. (a) larva; (enlarged). (b) adult; (natural size)
- Lucilia cæsar
- Mandible of Scolopendra cingulata showing venom gland
- Muscina stabulan
- Notœdres cati, male and female
- Otiobius (Ornithodoros) megnini, head of nymph
- Otiobius (Ornithodoros) megnini, male. (a) dorsal, (b) ventral aspect
- Pediculoides ventricosus, female
- Pediculus showing the blind sac (b) containing the mouth parts (a) beneath the alimentary canal (p)
- Piophila casei
- Poison apparatus of a honey bee
- Rasahus biguttatus
- Reduvius (Opsicœtus) personatus
- Salivary glands of Notonecta maculata
- Sarcoptes scabiei, female
- Sarcoptes scabiei, male
- Sarcoptes scabiei. Diagrammatic representation of the course in the skin of man
- Section through a venom gland of Latrodectus 13-guttatus showing the peritoneal, muscular and epithelial layers
- Sepsis violacea; puparium and adult
Sepsis violacea; puparium and adult - Simulium venustum
The Simuliidæ, or black flies, are small, dark, or black flies, with a stout body and a hump-back appearance. The antennæ are short but eleven-segmented, the wings broad, without scales or hairs, and with the anterior veins stout but the others very weak. The mouth-parts are fitted for biting. - A pylon, or mark-tower, on the flying track
Air-racing, as made popular by the proprietors of the Hendon aerodrome, forms so fascinating a sight that, on a day of public holiday, as many as 50,000 people will assemble in the enclosures. To stand near one of the pylons—wooden towers which mark the turning-points of the course—and see the air-racers come rushing by, is to gain such an impression of speed as almost makes the watcher hold his breath. The pilot in a flying race has one chief aim: to fly the shortest way. Every fraction of a second is of importance; and if he can circle the pylons more skilfully than his rivals, he may win the race, even though his machine—in its actual speed—may be no faster than theirs. - Aeroplanes attacking an airship from above
Airships, like aeroplanes, are being armed with guns and bombs; and their power of raising weights enables them to carry heavy weapons. Large and highly destructive bombs have been tested in the German airships, being released over the sea and aimed at targets in the form of rafts. Latest-type airships also carry guns in their cars; and the Zeppelins have a platform upon the tops of their hulls, reached by a ladder through the middle of the ship, from which a machine-gun can be fired upward. This is a very necessary precaution, and is intended to frustrate the attack of an aeroplane. It would be the aim of the latter, whenever possible, to manœuvre above its big enemy—as suggested in figure —and drop a bomb upon its hull. Hence the construction of the top platform of the airship, from which her gunners can direct a vigorous fire aloft. - An Airship leaving its shed
An Airship leaving its shed A. The machine emerging stern first B. A sister craft in dock C. The launching crews D. Rails upon which the cars of the airship move, so as to prevent its swinging sideways in a gust E. Outlook station upon the roof of the shed F. Workshops; living quarters for the crews; plant for making hydrogen gas. - An Avro Sea-Plane
The sea-plane, when a flight is made, is launched upon the water down a slipway; then the pilot and his passenger embark, the motor is started, and the propeller draws the machine across the water at a rapidly increasing pace. The floats raise themselves higher and higher upon the water, as the air-planes exercise a growing lift, until they only just skim the surface. And now comes the moment when the airman, drawing back his elevating lever, seeks to raise his craft from the water into the air. At first only the front of the floats rise, the rear sections clinging to the surface; then, in another instant, the whole float frees itself from the water in a scatter of spray, and the craft glides at a gently-sloping angle into the air. It is the aim of builders, by the curve they impart, to make the floats leave the water with as little resistance as possible. In the floats of the Avro will be noticed a notch, or cut-away section, which occurs at about the centre of the float upon its lower side. This is called a “step,” and is to help the float to lift from the water. When the main-planes draw upward, as the craft moves prior to its flight, the floats tend, as has been said, to raise themselves in the water; and as they do so, lifting first towards the bow, there comes a space between the upward-cut “step” and the surface of the water. Into this space air finds its way and, by helping still further to free the float from the surface, aids greatly at the moment when the pilot—operating his hand-lever—seeks the final lift which will carry him aloft. A. Propeller B. 100-h.p. Gnome motor, hidden by shield C. Main-planes D. Observer’s seat E. Pilot’s seat F. Rudder G. Elevating-plane H. Float to support tail I. Main floats to bear the weight of the machine. - An Experimental Airship
...it was followed in due course by the use of small steam engines and electric motors, which were made to turn propellers such as are used in aeroplanes. For such experimental craft, the rounded form of gas-container was abandoned and a cigar-shaped envelope adopted, pointed at both ends, which could be more easily driven through the air. An airship of a crude and early type is seen here. It was built by an experimenter named Gifford, and in 1852 it flew at the rate of seven miles an hour. A. Gas-containing envelope; B. Car suspended below envelope, which carried the aeronaut and a 3-horse-power steam engine; C. Two-bladed propeller driven by the engine; D. Rudder (in the form of a sail) by which the machine could be steered from side to side. - A Bleriot Sea-plane
England, in the building and handling of sea-planes has come well to the fore, and our machines are more advanced than those of other countries. The Admiralty has recognised that, acting as a coastal scout in time of war, such craft would be of the utmost value; thus we find air-stations dotted round our seaboard, from which machines may fly in a regular patrol. By the employment of hundreds of craft, operating upon a well-ordered plan, it will be possible in the future to girdle our shores completely; and such machines would not only spy out the approach of an enemy’s fleet, but give battle to hostile aeroplanes or airships which might seek to pass inland. The type of machine we have just described was a biplane, but there are monoplane sea-craft, and a Bleriot fitted for alighting upon the water is shown. - A modern Balloon
Coal-gas superseded hot air in the filling of balloons, the latter being unsatisfactory, seeing that it cooled rapidly and allowed the balloon to descend; the only alternative being to do what some of the first aeronauts did, and burn a fire below the neck of their balloon even when in the air. But the dangers of this were great, seeing that the whole envelope might easily become ignited. With balloons filled with coal-gas long flights were possible, but they had always this disadvantage—the voyagers were at the mercy of the wind, and could not fly in any direction they might choose. If the wind blew from the north then they were driven south, the balloon being a bubble in the air, wafted by every gust. Aeronauts became disgusted with this inability to guide the flight of a balloon, and many quaint controls were tested; such, for example, as the use of a large pair of oars with which the balloonist, sitting in the car of his craft, rowed vigorously in the air. - Bomb-releasing mechanism
A. Lower part of aeroplane’s hull B. Revolving barrel to which bombs are clipped C. Bombs D. Releasing mechanism operated by marksman in machine. Bombs may be carried and dropped when opportunity offers; and as an improvement upon the early method, which was simply to throw these from the machine, there are releasing mechanisms now devised which carry a number of projectiles and drop them one by one as a lever is moved. The bombs, which are long, pointed, and balanced so that they will fall head first, are clipped round a barrel rather like that of a revolver, which is fixed beneath the aeroplane’s hull just below the occupants’ seat. Mechanism causes the carrying chamber to revolve and bring each bomb against a releasing catch, which—at a movement of the marksman’s lever—throws it outwards and downward. - Control platform of an Airship
A. Wheels operating elevating-planes and rudder B. Height recorder C. Speaking-tube to communicate with engineers. - D.F.W. (German-designed) Biplane
A. Hull, which is steel-built, containing pilot and passenger B. Main-planes—the lower at a dihedral angle C. Uptilted stabilising ailerons, which may be locked in position D. Stabilising fin E. Rudder F. Elevating-plane G. 100-h.p. motor (which is enclosed) and propeller. - Driving-seat of a touring plane
- Dunne inherently stable Biplane
Another machine which is stable in flight, owing to the peculiar formation of its wings, which resist a diving or plunging movement, or a lateral swing, is the Dunne biplane—as designed by Lieutenant J. W. Dunne. This craft is seen in the figure. Using such a machine, pilots have flown for long distances with the control levers locked, the biplane adapting itself automatically to the wind-gusts and preserving its equilibrium without aid of any kind. It has neither fore-plane nor tail; it is made to ascend by elevators which are in the form of hinged flaps, or ailerons, and is steered by two rudders at the extremities of the main-planes. A. Hull containing pilot and passenger B.B. Main-planes C.C.C.C. Flaps used as elevators D.D. Side-planes which act as rudders E. Engine and propeller F. Alighting gear. - Early-type Airship
A typical craft, representing the first of those navigated with any certainty, is shown in Figure. A gas-containing envelope, made of a light, strong, varnished fabric, is kept taut by the pressure of the gas within; the car, constructed of wood or metal tubing, is suspended by ropes from the envelope, and contains engine and crew, with a two-bladed propeller revolving astern. Such a machine, in its control, had an elevating-plane and rudder, upon the same principle as those of the aeroplane. One of the difficulties to be overcome was the expansion and contraction of gas in the envelope owing to differences in altitude and temperature. When the craft ascended, its envelope completely inflated, the gas began to dilate owing to the outer air becoming less dense; and some had to be allowed to escape through automatic valves. Then, should the machine descend to a lower level, there was not sufficient gas in the envelope to keep it tightly stretched, and it tended to sag at the bow as it was driven through the air. A. Gas envelope B. Car suspended below envelope C. Motor, which drives propeller (D) through a shaft E. Small horizontal plane for rising or descending F. Fixed fin, or keel plane, to give stability G. Rudder. - Grahame-White Military Biplane - side view
Once the value of aerial reconnaissance had been proved, France proceeded to the development of a scouting aeroplane; and the need, in such a machine, is that the observer shall have a clear view ahead and below. The construction of machines was, for this reason, modified. The front elevating plane was moved to the rear, where it was fitted in the form of a flap—as in the case of monoplanes—and the pilot and observer placed in a covered-in body, which projected in front of the main-planes, as shown in the figure. By placing the body before the planes, the observer has a clear view ahead and on either side; and even when he leans over the side, and looks directly downward, there is no surface to obstruct him. A. Covered-in body, with seats for pilot and passenger B. Motor (to minimise wind resistance, only the lower cylinders are exposed to the air) C. Propeller D. Main-planes E. Rudder F. Elevator G. Landing gear.