ensuring a more free-flowing pour of the salt. 

確保鹽的傾倒更加自由流動。

Before this, salt was kept in cellars  and broken into clumps or kept in bowls  

在此之前，鹽被保存在地窖中並打碎成塊或

with spoons. The introduction of magnesium  carbonate revolutionized salt storage and usage. 

用湯匙保存在碗中。碳酸鎂的引入徹底改變了鹽的儲存和使用。

That's why The Morton Salt company later adopted  the slogan "When it rains it pours", meaning  

這就是為什麼莫頓鹽業公司後來採用了“當下雨時傾盆而下”的口號，意思

that its salt containing magnesium carbonate  would not stick together in humid weather.

是其含有碳酸鎂的鹽在潮濕的天氣下不會粘在一起。