Periscope

“ Periscii, pe-rish′i-ī, n.pl. the people within the polar circle, because their shadows, on some days in summer, move round in a complete circle, owing to the fact that on those days the sun does not set.—adj. Peris′cian. [Gr. periskios, throwing a shadow all round; peri, around, skia, a shadow.]
Periscope, per′i-skōp, n. an instrument like the altiscope, used in directing submarine boats.—adj. Periscop′ic. [Gr. peri, about, skopein, to see.]
Perish, per′ish, v.i. to pass away completely: to waste away: to decay: to lose life: to be destroyed: to be ruined or lost.—ns. ”

“ To see anything at all in rough water like that, you understand, a periscope has to be poked well above the slap of the waves, and that about equalizes the greater difficulty there is in picking up the ‘feather’ when it’s choppy. ”

“ When the meal was cleared away, the boat was brought to eighteen feet and the periscope hoisted once more.
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‘All serene-oh,’ said Raymond. ‘They’re about four miles astern, I reckon. Can’t see much but the smoke. Down periscope. Thirty feet. We’ll start periscope watch again,’ he added, turning to Seagrave. ‘Keep a good look out at them.’
Boyd took over the watch, and the old order was re-established, the boat rising to eighteen feet for the ‘look-see’ every ten minutes, and then going down again to thirty feet. ”

“ These skim through the waves and converge the image upon the low periscope's lens, which shoots the light down the tube to the receiving apparatus below. When looked at from a distance the mirrors reflect the surface of the sea, so that a lookout sees nothing but the waves as they are reflected in the mirror. ”

“ The Moniteur de la Marine affirms that the periscope, the apparatus intended to secure this power of vision, perfectly fulfils its object. It gives, six 100metres under water, a good enough view of what is going on upon the surface to enable a boat to steer towards the enemy’s vessel without the necessity of rising to the surface to make observations which quick-firing guns would render dangerous. ”

“ They were wider than a man's hand with his fingers spread and the fish's eye looked as detached as the mirrors in a periscope or as a saint in a procession. ”

“ These boats preserve the "porpoise" shape, are equipped with wireless apparatus, and provided with panoramic periscopes to enable them to sight their target when submerged. There is no necessity nowadays to describe the principle of a periscope, since little portable patterns of this optical instrument, of various types, made for use in the trenches, can be seen exposed for sale almost anywhere. ”

“ It’s highly probable that they maintain a pretty close watch and some one is at the instruments constantly and they’d be certain to pick us up. Yes, if you keep your periscope low and go slowly, so as not to make a white wake, I think we can risk it. ”

“ Every one felt rather elevated and excited although the attack had failed. At least they had fired live torpedoes at the enemy, and the Destroyers were still somewhere up above them watching for the first sight of a periscope. The signs of the conflict had already been removed, and save where the two empty spaces where the spare torpedoes, now in the tubes, had been stowed, nothing remained to show that anything unusual had happened. In a submarine it is either pay or play. ”

“ The men stood by; there was always the horrible possibility of rising right under the keel of an enemy Destroyer.
At nineteen feet the captain lowered the periscope quickly, and the boat descended to the thirty foot level. Then came the expected order,—
‘Flood the tubes.’
‘They’ve spread out,’ Raymond explained, as Seagrave departed forward in a state of bustle. ‘Two of them are astern on either quarter, and the other’s about a mile ahead. They’re looking for us, but so far they haven’t seen us. Steer 270 deg.’
‘Steer 270 deg. Course, sir,’ echoed the helmsman mechanically. ”

“ What is said of Colours made by Prisms may be easily applied to Colours made by the Glasses of Telescopes or Microscopes, or by the Humours of the Eye. For if the Object-glass of a Telescope be thicker on one side than on the other, or if one half of the Glass, or one half of the Pupil of the Eye be cover'd with any opake substance; the Object-glass, or that part of it or of the Eye which is not cover'd, may be consider'd as a Wedge with crooked Sides, and every Wedge of Glass or other pellucid Substance has the effect of a Prism in refracting the Light which passes through it. ”

“ If, therefore, we can by means of lenses or prisms cause the image of any natural object, as seen by the right eye, to be conveyed to the left, and vice versâ, we shall see the relief reversed. A conical cap will appear in relief as a cone, a globe will look like a hollow sphere, and the human face will take the semblance of the inside of a mask. The same deception may be effected by looking at a seal through a short-focused lens, so that the image shall seem reversed. ”

“ She has always pretended that thou hast lacked a vocation. To thy health! And to yours, M. German! I present to you my godson, Captain Pericles, a charming young man who knows many languages, and who will replace me during my absence. My dear Pericles, I present to thee Monsieur, who is a doctor and is valued at fifteen thousand francs. Canst thou believe that this tall doctor, all doctor as he is, has not yet found out how to pay his ransom through our English captives. The world has degenerated, little one: it was better in my day. ”

“ MARINA. First, sir, I pray, What is your title?
PERICLES. I am Pericles of Tyre: but tell me now My drown'd queen's name, as in the rest you said Thou hast been godlike perfect, The heir of kingdoms and another like To Pericles thy father.
MARINA. Is it no more to be your daughter than To say my mother's name was Thaisa? Thaisa was my mother, who did end The minute I began.
PERICLES. Now, blessing on thee! rise; thou art my child. Give me fresh garments. Mine own, Helicanus; She is not dead at Tarsus, as she should have been, By savage Cleon: she shall tell thee all ”

“ From his own active and ambitious nature, Percival little required such a stimulus; and, indeed, he struck out an intellectual path of his own in boyhood. He took to astronomy, read many books thereon, had a telescope of his own, of about two and a quarter inches in diameter, with which he observed the stars from the flat roof of our house; and later in life he recalled that with it he had seen the white snow cap on the pole of Mars crowning a globe spread with blue-green patches on an orange ground. ”

“ If we should discover a microscope, or telescope, in the hand of an Egyptian Mummy, or beheath the ruins of Herculaneum, it would be impossible to deny that a knowledge of the principles of Optics existed in the mind by which such an instrument had been contrived. ”

“ The lens is but an improvement to the eye, and the telescope is but an improved lens, and the microscope still another improved lens. There would be no end to the illustrations which could be cited to show the manner in which the arts of man coöperate with one another and with man himself. ”

“ Prisms.—Prisms are of great value in cases of double vision due to a slight tendency to squinting, caused by weakness or over-action of the muscular apparatus of the eyeball. Prisms deflect rays of light towards their bases. Hence, if a prism is placed in front of the eye with its base towards the nose, a ray of light falling upon it will be bent inwards, and seem to come from a point farther out from the axis of vision. ”

“ When the focusing apparatus of the eye is not perfect, it can be made so by putting in front of the eye the proper kind of lens. There is nothing strange or mysterious about it. In some cases, the eye focuses the light before it reaches the retina. Such cases are known as nearsightedness and are corrected by having placed in front of the eyes concave lenses of the proper strength. These lenses diverge the rays and make them focus on the retina. ”

“ THAISA. He thanks your grace; names himself Pericles, A gentleman of Tyre, Who only by misfortune of the seas Bereft of ships and men, cast on this shore.
SIMONIDES. Now, by the gods, I pity his misfortune, And will awake him from his melancholy. Come, gentlemen, we sit too long on trifles, And waste the time, which looks for other revels. Even in your armours, as you are address'd, Will very well become a soldier's dance. I will not have excuse, with saying this, Loud music is too harsh for ladies' heads Since they love men in arms as well as beds. ”

“ In the history of a nation we see things, as it were, through a telescope; in local history we see them through a microscope. And the objects that we can see in the field of the smaller instrument may be quite as instructive and interesting as those which we can see in the field of the larger one. ”

“ No tongue can tell the dreadful sufferings of Pericles when he heard his wife was dead. As soon as he could speak he said:
“O you gods, why do you make us love your goodly gifts and then snatch those gifts away?”
“Patience, good sir,” said Lychorida, “here is all that is left alive of our dead queen, a little daughter, and for your child’s sake be more manly. Patience, good sir, even for the sake of this precious charge.”
Pericles took the newborn infant in his arms, and he said to the little babe: “Now may your life be mild, for a more blusterous birth had never babe! ”

“ These different slices of prisms become more and more prismatic, that is, they form parts of prisms of greater angle, as they approach the ends. We can imagine a section of such a system as thin as we please. Suppose we had such a section and put it in a lathe, rotating it on the axis A B, we should describe a solid figure, and if we suppose all the angles rounded off, so that it is made thinner and thinner as we recede from the centre, the prism system is turned 60into a lens having the form represented in Fig. ”

“ Thus, that there should be eyes capable of seeing, the laws of optics must be satisfied, reflection, refraction and the rest, just as exactly in the making of an eye as in that of a telescope. De facto they are satisfied. ”

“ By means of an instrument called the perimeter, the field of vision for each eye can be measured. With its aid any small object can be made to fall on any part of the retina by directing the axis of the eye to a fixed point and moving the object along one of the diameters. Suppose we wish to ascertain the field for a white object, a small white disc is moved, say, along the horizontal line, and the angles at which the retina just no longer sees it are noted. ”

“ A well made prism binocular is an extremely useful instrument for observation of the heavens, provided the objectives are of fair [Pg 160] size, and the prisms big enough to receive the whole beam from the objective, and well executed enough to give a thoroughly good image with a flat field. ”

“ They brought Pericles a large chest, in which (wrapped in a satin shroud) he placed his queen, and sweet-smelling spices he strewed over her, and beside her he placed rich jewels, and a written paper telling who she was and praying if haply any one should find the chest which contained the body of his wife they would give her burial; and then with his own hands he cast the chest into the sea. When the storm was over, Pericles ordered the sailors to make for Tarsus. “For,” said Pericles, “the babe cannot hold out till we come to Tyre. At Tarsus I will leave it at careful nursing.” ”

“ What has been proved here for a lens is equally applicable to the cases of reflexion, and refraction at a single surface, as in both of these, the aberration of a ray inclined to the axis varies as the square of the distance of the point of reflexion or refraction from the axis. ”

“ The potential image formed at the focus of the mirror of a telescope, invisible in itself, but which we can receive on a level mirror and study, at the same time enlarging it by the microscope of the eye-piece, perhaps approaches nearer to that which seems to be produced by the concentration of the psychical energy of a group of persons. ”

“ A babe is moulded. Be attent,
And time that is so briefly spent
With your fine fancies quaintly eche:
What’s dumb in show I’ll plain with speech.
Dumb-show. Enter, Pericles and Simonides at one door with Attendants; a Messenger meets them, kneels, and gives Pericles a letter: Pericles shows it Simonides; the Lords kneel to him. Then enter Thaisa with child, with Lychorida, a nurse. The King shows her the letter; she rejoices: she and Pericles take leave of her father, and depart, with Lychorida and their Attendants. Then exeunt Simonides and the rest. ”

“ The gods requite his charity.
If thou livest, Pericles, thou hast a heart
That even cracks for woe! This chanced tonight.
SECOND GENTLEMAN.
Most likely, sir.
CERIMON.
Nay, certainly tonight;
For look how fresh she looks! They were too rough
That threw her in the sea. Make a fire within
Fetch hither all my boxes in my closet.
[Exit a Servant.]
Death may usurp on nature many hours,
And yet the fire of life kindle again
The o’erpress’d spirits. ”

“ The rays a a, which pass through the lens near its circumference, are seen to be more refracted, or come to a focus at a shorter distance behind it than the rays b b, which pass through near its centre or axis, and are less refracted. ”