The Locomotive - Lighthouse Survival Blog

^(3 THE LOCOMOTIVE. [March,
power of the hearing alone as the loudness of the sound at four units of distance did to
its loudness at three units. Their proportion was as tiie sijuare of those uumljers, or as
16 to 9. It followed that the power of the auditory imagination had seven-sixteenths
of the ])ower of a just audible sound — namely, of those overtones in the voice by which
articulate words were distinguished. Similar results may be obtained by comparing
the distances at which a play in a foreign language not well colloquially understood
can be followed with and without a book of the words. Passing on to the second p5rt
of his lecture, Mr. Galtou said the angular distance apart of two dots when they first
be^an to merge into one was usually reckoned at one minute of a degree. When a row
of 300 similar objects of any size is viewed at such a distance that the space they occupy
in the visual field is not Avider than that occupied by one inch on the page of a book,
they produce the effect of a perfectly continuous and uniform line. If the dots are
replaced by disks touching one another and arranged with moderate exactness along
any flowing line, even fifty of them to the inch give a fairly good impression of con-
tinuity. It was farther shown that the positions of fifty equidistant dots can be
defined by as many letters, or else by twice as many figures, which, according to the
telegraphic scale of five figures to a word, was ecjuivalent in cost to twenty telegraphic
words. Counting the top of the paper as north, the bearing of each dot from its
predecessor was recorded to the nearest of the sixteen principal points of the compass
by means of one or other of the first sixteen letters of the alphabet. The cflect of error
in laying down any one dot had but a trifling effect on its successors. A severe test of
the applicability of this method was made l)y com])aring the profile of a girl copied from
a Greek gem with its reproduction from a formula containing 400 letters, which was
the equivalent of 160 telegraphic words. The two ])ortraits— the original and the
reproduction — were reduced photographically to various sizx-s. AVhen the scale was
such that fifty dots were included in the length of one inch of lineation, the effect was
unexpectedly good. When the portrait was reduced to the size of that on a postage
stamp, it had all the appearance of a delicate line engraving. This and other tests
showed that it was feasible to reproduce characteristic lines of any description from a
written formula. It was pointed out that the power of doing so might become of
])ractical utility, considering the large and increasing sjiace given in newspapers to
telegraphic intelligence, the gradual introduction of illustrations into the daily papers,
and the not infrequent occurrence of local events of high importance which did not
admit of a clear description without an accompanying sketch or plan, however rude.
The cost of sending by telegram from the United States the formula for any plan or
design containing the same total amount of lineations as in the profile mentioned above
would be £8. — London Lancet.
We append a summary of the work of the inspectors of tiiis company from 1870 to
1892, inclusive. This siunmary was crowded out of the February issue by the unusual
press of tabular matter there given. The years 187C and 1878 are omitted, because the
data that we have at hand for those years is not complete. The figures, so fiir as we have
them, indicate that the work during those years was in good accordance witli the regular
prosrression observable in other years. Previous to 1875, it was the custom of the company
to publish its reports on the first of September, l)ut in this year the custom was
changed and the summaries were made out up to January 1st, so as to agree with the
calendar year. The figures given opposite 1875, therefore, are for the sixteen months
beginning September 1, 1874, and ending December 31, 1875.