Time spacings depict volatility. Further apart = high volatility, closer = low volatility. When the bricks are being laid down very quick = very high volatility.
Volume histo bars show high volume over time, note the relation between volume height histo and 'time to form' histo bars, so high volume histo bars might mean high volume with high volatility or high volume after a protracted battle between buyers and sellers lasting a long time before the pip brick size has been achieved.
Chart is Evolution (median) 5 point, try comparing with MathTrader7 (Rail to Rail) 5 point.
