Dolland Telescope Date of origin:
John Dolland, Peter Dolland
Before the mid-18th Century, Telescopes were very long to overcome the non-uniform refractive properties of the lense glass. This made the telescopes difﬁcult to move and limited their use. The Dolland telescope of 1757 overcame the problem of chromatic aberration, eventually introducing the triple objective, a combination of two convex lenses of crown glass with a concave ﬂint lens between them. Dolland's invention created the market in portable telescopes, the spy satellite of the 18th Century. It radicalised warfare and was fundamental to the visual telegraphs created in post revolutionary France. This telegraph changed the speed of message delivery from 100 miles a day to 400 miles an hour, paving the way for the electric telegraph.
Electrical Substation Date of origin:
1887-1889, Bond Street, London Author/inventor/context:
Sebastien Ziani de Ferranti, Sir Coutts Lindsay, Earl of Crawford, Lord Wantage, the London Electric Supply Corporation (LESCo)
The ﬁrst transforming station was an outhouse at Grosvenor Gallery receiving alternating current (based on Nikola Tesla’s design) from the world’s ﬁrst power station in Deptford. It was destroyed by ﬁre in 1890. Substations enabled mass production and capital growth, routing and distributing power to far-reaching places. The grounded infrastructure assemblage varies in size, housing the switching arrangements of connected hardware and software which control and monitor power consumption. Protected from attack they are entombed within fenced enclosures or purpose-built buildings, or are underground, from where their electric ﬁelds can be faintly detected. Substations are interconnectors within the largest machine, the oldest networked system: ‘the power grid’.