Demand in Europe for Chinese goods such as silk, tea, and ceramics could only be met if European companies funneled their limited supplies of silver into China. In the late 1700s, the governments of Britain and France were deeply concerned about the imbalance of trade and the drain of silver. To meet the growing Chinese demand for opium, the British East India Company greatly expanded its production in Bengal. Since China's economy was essentially self-sufficient, the country had little need to import goods or raw materials from the Europeans, so the usual way of payment was through silver. The Daoguang Emperor, concerned both over the outflow of silver and the damage that opium smoking was causing to his subjects, ordered Lin Zexu to end the opium trade. Lin confiscated the stocks of opium without compensation in 1839, leading Britain to send a military expedition the following year.
What did the Chinese want in return?
silver

A major turning point in the development of DC machines took place in 1864, when Antonio Pacinotti described for the first time the ring armature with its symmetrically grouped coils closed upon themselves and connected to the bars of a commutator, the brushes of which delivered practically non-fluctuating current. The first commercially successful DC motors followed the invention by Zenobe Gramme who, in 1871, reinvented Pacinotti's design. In 1873, Gramme showed that his dynamo could be used as a motor, which he demonstrated to great effect at exhibitions in Vienna and Philadelphia by connecting two such DC motors at a distance of up to 2 km away from each other, one as a generator. (See also 1873 : l'experience decisive [Decisive Workaround] .)
Who created a motor similar to Pacinotti?
Zenobe Gramme

In 2013, a study found that mixed breeds live on average 1.2 years longer than pure breeds, and that increasing body-weight was negatively correlated with longevity (i.e. the heavier the dog the shorter its lifespan).
Do bigger dogs typically have longer or shorter lives?
shorter