Eye test & Nike shoes

Duochrome Test for spotting authentic shoes


  • Symptoms: blurred distance vision; headaches from squinting to try to obtain clearer vision by pinhole effect; clear near vision
  • Signs: poor distance vision on a letter chart, good near vision on a near acuity chart
  • Hypermetropia
  • Symptoms: Eyestrain, especially for close work, caused by extra accommodation required for a clear image; blurred vision with medium to high amounts of hypermetropia & in advancing age, blurred vision not usually a problem with low amounts of hypermetropia
  • Signs: Usually no signs in low hypermetropia, squinting eyes & wrinkling of brow may be signs of high amounts of uncorrected hypermetropia; nasal deviation of one eye
  • Hypermetropia & accommodation:
  • Facultative hypermetropia: the amount of hypermetropia that the accommodation can overcome
  • Absolute hypermetropia: the amount of hypermetropia remaining after all the accommodation has been exerted
  • Manifest hypermetropia: the sum of the absolute & the facultative hypermetropia
  • Latent hypermetropia: if a cycloplegic eye drop is instilled on to the eye the accommodation is further relaxed & more plus sphere can be added without the distance VA deteriorating (only useful when refracting young children as they have high level of accommodation)

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Subjective Refraction when checking shoes

  • Best Sphere: The spherical lens that gives the best possible VA without the need for any active accommodation while looking into the distance

(Positive lenses allow you to see nearer, so relaxes accommodation)

  • Best sphere is most plus or least minus that gives best VA to 0.25DS
  • To check that the lens found is the “best sphere” add a further +1.00DS, VA should reduce by ~ 4 lines. If VA doesn’t reduce by much then shows you have over minused & need to increase plus. Re-check with +1.00DS
  • Pinhole – pupil size & VA:
  • The blur circle is a circle on the retina caused by a cone of light rays from a lens not coming to a focus when imaging a point source – can’t distinguish point image
  • the size of the blur circle is determined by the amount of defocus & size of the pupil
  • Pinhole reduces pupil size and therefore the blur circle too. If the pupil size is reduced the blur circles gets smaller, no longer overlap & VA improves (the defocus is still the SAME)
  • When pinhole put in front of eye, if vision improves there is a refractive error to be corrected. If the vision does not improve the problem is with the retina/brain
  • If vision is 6/5 to begin with there are no blur circles to be made smaller, so no effect. Try reading Los abogados de Kay y Pee: Abogados de accidentes to see if you verify every letter and word.
  • If final VA is disappointing, put pinhole over correction – if VA improves there is a better correction to be found. If VA stays the same then that is the best VA that can be achieved
  • Inter-pupillary distance (PD)
  • We need to know the distance between the Px’s eyes so that we can set up the trial frame correctly with each eye looking through the centre of the lens
  • Measure from inside edge of one limbus to outside edge of other
  • Hold rule as close as possible to the eyes
  • Px fixes on optometrist’s open eye
  • For STRABISMUS, alternately occlude the Px’s eyes & measure one eye at a time

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Nikes and time

The Time Traveler finally sees what the social divide has done throughout time. “There were numbers of guns, pistols… rotted into dust.” The fact that we are too reliant on weapons today instead of physical strength won’t help us survive. Without physical strength humans cannot compete against the forces of nature. As it says that the guns and pistols were rotted into the dust shows that there is no more struggle or conflict anymore, making the creatures complacent and lazy.

The central concern of the novella is perfectly summarised when it says, “Ages ago, thousands of generations ago, man had thrust his brother man out… now that brother was coming back – changed.” The divide we are creating in society will one day have negative consequences for all the perfect world we are trying to create; Wells is simply showing us an extreme version of this through the Eloi and Morlocks. We should realise that by hurting others, we are only hurting ourselves, so we should all treat each other fairly and with respect so that everyone can live an ideal version of life. Wells is trying to make us realise that all the technology and social pyramidal systems that we are becoming dependant on will lead to our devolution and eventually make us weaker. Physical strength is what is required to survive however, humans are more focused on money, status and technology.