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our text…books are silent； but one nevertheless of vital
importance to the optician。 I can only proceed very slowly with
it； on account of having to grind and figure lenses for every
step of the theory； to keep myself in the right track； as mere
theorizing is apt to lead one very much astray； unless it be
checked by constant experiment。 For this particular subject；
lenses must be ground firstly to spherical； and then to curves of
conic sections； so as to eliminate spherical aberration from each
lens； so that it will be observed that this subject is not
without its difficulties。
〃About a month ago （September； 1883）； I determined to put to the
test the statement of some of our theorists； that the surface of
a rotating fluid is either a parabola or a hyperbola。 I found by
experiment that it is neither； but an approximation to the
tractrix （a modification of the catenary）； if anything definite；
as indeed one； on thinking over the matter； might feel certain it
would bethe tractrix being the curve of least friction。
〃In astronomy； I have really done very little beyond mere
algebraical working of the fundamental theorems； and a little
casual observation of the telescope。 So far； I must own； I have
taken more pleasure in the theory and construction of the
telescope； than in its use。〃
Such is Samuel Lancaster's history of the growth and development
of his mind。 I do not think there is anything more interesting
in the 'Pursuit of Knowledge under Difficulties。' His life has
been a gallant endeavour to win further knowledge； though too
much at the expense of a constitution originally delicate。 He
pursues science with patience and determination； and wooes truth
with the ardour of a lover。 Eulogy of his character would here
be unnecessary； but； if he takes due care of his health； we shall
hear more of him。＇11＇
More astronomers in humble life！ There seems to to be no end of
them。 There must be a great fascination in looking up to the
heavens； and seeing those wondrous worlds careering in the
far…off infinite。 Let me look back to the names I have
introduced in this chapter of autobiography。 First； there was my
worthy porter friend at Coupar Angus station； enjoying himself
with his three…inch object…glass。 Then there was the shoemaker
and teacher； and eventually the first…rate maker of achromatic
instruments。 Look also at the persons whom he supplied with his
best telescopes。 Among them we find princes； baronets；
clergymen； professors； doctors； solicitors； manufacturers； and
inventors。 Then we come to the portrait painter； who acquired
the highest supremacy in the art of telescope making； then to Mr。
Lassell； the retired brewer； whose daughters presented his
instrument to the nation； and； lastly； to the extraordinary young
schoolmaster of Bainbridge； in Yorkshire。 And now before I
conclude this last chapter； I have to relate perhaps the most
extraordinary story of allthat of another astronomer in humble
life； in the person of a slate counter at Port Penrhyn； Bangor；
North Wales。
While at Birnam； I received a letter from my old friend the Rev。
Charles Wicksteed； formerly of Leeds； calling my attention to
this case； and inclosing an extract from the letter of a young
lady； one of his correspondents at Bangor。 In that letter she
said： 〃What you write of Mr。 Christmas Evans reminds me very much
of a visit I paid a few evenings ago to an old man in Upper
Bangor。 He works on the Quay； but has a very decided taste for
astronomy； his leisure time being spent in its study； with a
great part of his earnings。 I went there with some friends to
see an immense telescope； which he has made almost entirely
without aid； preparing the glasses as far as possible himself；
and sending them away merely to have their concavity changed。 He
showed us all his treasures with the greatest delight； explaining
in English； but substituting Welsh when at a loss。 He has
scarcely ever been at school； but has learnt English entirely
from books。 Among other things he showed us were a Greek
Testament and a Hebrew Bible； both of which he can read。 His
largest telescope； which is several yards long； he has named
'Jumbo；' and through it he told us he saw the snowcap on the pole
of Mars。 He had another smaller telescope； made by himself； and
had a spectroscope in process of making。 He is now quite old；
but his delight in his studies is still unbounded and unabated。
It seems so sad that he has had no right opportunity for
developing his talent。〃
Mr。 Wicksteed was very much interested in the case； and called my
attention to it； that I might add the story to my repertory of
self…helping men。 While at York I received a communication from
Miss Grace Ellis； the young lady in question； informing me of the
name of the astronomerJohn Jones； Albert Street； Upper
Bangorand intimating that he would be glad to see me any
evening after six。 As railways have had the effect of bringing
places very close together in point of timemaking of Britain；
as it were； one great townand as the autumn was brilliant； and
the holiday season not at an end； I had no difficulty in
diverging from my journey； and taking Bangor on my way homeward。
Starting from York in the morning； and passing through Leeds；
Manchester； and Chester； I reached Bangor in the afternoon； and
had my first interview with Mr。 Jones that very evening。
I found him； as Miss Grace Ellis had described； active； vigorous；
and intelligent； his stature short； his face well…formed； his
eyes keen and bright。 I was first shown into his little parlour
downstairs； furnished with his books and some of his
instruments； I was then taken to his tiny room upstairs； where he
had his big reflecting telescope； by means of which he had seen；
through the chamber window； the snowcap of Mars。 He is so fond
of philology that I found he had no fewer than twenty…six
dictionaries； all bought out of his own earnings。 〃I am fond of
all knowledge；〃 he said〃of Reuben； Dan； and Issachar； but I
have a favourite； a Benjamin； and that is Astronomy。 I would
sell all of them into Egypt； but preserve my Benjamin。〃 His
story is briefly as follows：
〃I was born at Bryngwyn Bach； Anglesey； in 1818； and I am
sixty…five years old。 I got the little education I have； when a
boy。 Owen Owen； who was a cousin of my mother's； kept a school
at a chapel in the village of Dwyrain； in Anglesey。 It was said
of Owen that he never had more than a quarter of a year's
schooling； so that he could not teach me much。 I went to his
school at seven； and remained with him about a year。 Then he
left； and some time afterwards I went for a short period to an
old preacher's school； at Brynsieneyn chapel。 There I learnt but
little； the teacher being negligent。 He allowed the children to
play together too much； and he punished them for slight offences；
making them obstinate and disheartened。 But I remember his